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Prof. Mahmoud A. Melehy
local time: 2024-03-29 05:18 (-04:00 DST)
Prof. Mahmoud A. Melehy (Abstracts)
Titles Abstracts Details
  • Thermodynamic Generalization to Interfacial Systems of Einstein Theory of Brownian Motion (2011) [Updated 1 decade ago]

    This talk discusses the rationale for accounting in thermodynamics for the particle momentum, associated with thermal motion (thermal momentum). The resulting theory is a field formulation, which has numerous, novel, fundamental theoretical and applied consequences of interdisciplinary nature. The applications include diversified problems that relate to: semiconductor diodes, solar cells, meteorology, and surface and interfacial phenomena. Experimental data related to semiconductor diodes are compared with two theories: one based on classical thermodynamics that ignores the particle thermal momentum and thermodynamics that accounts for that fundamental quantity. The latter theory is in accurate agreement with the experimental results.


  • Generalization and New Applications of Einstein's Theory of Brownian Motion (2005) [Updated 1 decade ago]

    Above absolute zero, molecules, ions, conduction electrons and other particles, in any liquid, gas, or solid, have significant thermal motion, which can be translational, vibrational, and/or rotational. For example, in an ideal H2 gas in equilibrium, at 300 K, the root-mean-square of the translational velocity, per particle, vrms is about 1.93 km/s. More significantly, for conduction electrons in copper, vrms is about 1.22 x 103 km/s. Since all such particles have finite masses, then thermal motion is inevitably associated with highly ap-preciable particle kinetic energy and momentum. Classical thermodynamics as evolved in the 19th century, has accounted for, among common parameters, the particle kinetic energy, while totally ignoring the particle thermal momentum. In 1905, however, in his theory of Brownian motion, Einstein introduced that important thermophysical concept into thermodynamics. Specifically, he calculated the force acting on particles suspended, or dissolved in a liquid, under the diffusion action. To derive that force, Einstein followed substantially the same mechanical approach used by Maxwell in 1960, who determined the force acting on a ideal gas diffusing in another. This paper shows that a generalized form of the Maxwell-Einstein diffusion force, applicable to most systems, can be derived thermodynamically, by accounting for the time-rate of change of the particle thermal momentum. The resulting, generalized diffusion force fD, per particle, has proved to be highly significant, particularly in interfacial systems. Determining how fD would interact in any system, under equilibrium and nonequilibrium conditions, with electric, and other fields involving action-at-a-distance, has led to a new general thermodynamic theory.1,2 Applying that theory to semiconductor diodes and solar cells has predicted the voltage-current characteristics of such devices. Theory has accurately been corroborated by extensive experimental characteristics reported by some 27 authors in a period exceeding a quarter century.1,2 The experiments were conducted in the temperature range: 4.2 and 800K. In one experiment the maximum-to-minimum current ratio exceeded 10 orders of magnitude. More recently, the present thermodynamic theory has revealed a new fundamental result: that the first and second laws require the existence of electric charges at almost all surfaces, membranes, and other interfaces. This interesting result, which is verifiable experimentally, can now explain numerous, diversified phenomena, of interdisciplinary interest,3 such as: surface tension, capillarity, which is essential to plant and animal life, light particle adhesion, the suspension of fog, atmospheric electricity, the forces that shape tornados, and even one phenomenon first reported in Ancient Greece, by Thales of Miletus, some 26 centuries ago: the generation of static electricity by rubbing two different insulators against one another. The thermodynamically required interfacial electrification further confirms Newton's speculation in the 18th century that interfacial forces might be electric in nature.

    References:

    1. M. A. Melehy, Physics Essays, 10, (2), 287-303 (1997).
    2. idem, Foundations of the Thermodynamic Theory of Generalized Fields," (Baltimore: Mono, 1973).
    3. idem, Physics Essays, 11, (3), 430-443 (1998); 14, (1), 49-58 (2001).

  • Thermodynamic Basis of Electricity in Cancer Growth and other Systems Changing Structure (2004) [Updated 1 decade ago]

    Generalization by this author of Einstein's theory of Brownian motion has revealed that the first and second laws of thermodynamics require the electrification of surfaces, membranes, and other interfaces.  This interesting result explains numerous phenomena, including capillarity, adhesion, atmospheric electricity, coalescence of drops, to mention a few examples.  Accordingly, upon phase change, healing of tissue, and growth of cancer cells, the flow of electric current is a thermodynamically required phenomenon.


  • Energy Stored in a Gravitational Field (2001) [Updated 7 years ago]

    It is well known that there is energy stored in any space penetrated by an electric, or a magnetic field. This paper, however, shows that there is, likewise, energy stored in any space penetrated by a gravitational field. By a non-relativistic method, we calculate the energy stored, wg, in a planetary gravitational field, per unit volume. Near the surface of Planet Earth, the result shows that wg is approximately 15.9 Megawatt-hour/cubic-meter. How much of this enormous amount of energy can be extracted is a difficult question to answer.


  • Thermal Momentum in Interfacial Thermodynamics (2000) [Updated 1 decade ago]

  • A New Look at Thermodynamics, Part 1: Theory (2000) [Updated 1 decade ago]

    Thermodynamic equilibrium is most generally characterized by the principle of microscopic reversibility,l which matured some fifty years after thermodynamics was formulated. This paper shows that in light of that important principle the classical thermodynamic formulation would be valid only if the system particles have no thermal motion.2 Such a condition can only be realized at absolute zero. But above that temperature, particles acquire thermal motion and momenta. The rate of change of the particle thermal momentum, per unit area, is a mechanical pressure, which can profoundly vary across an interface. Particles transported through such sites can then be subjected to highly significant mechanical forces. Accounting for these forces leads to fundamental consequences, including: (1) a distinction between motive and dissipative forces/processes; and (2) the need to invoke the conservation of energy principle to determine how motive and dissipative forces/processes interact. Consequently, the state of equilibrium is rendered more detailed than has heretofore been possible to express. Specifically, at equilibrium, each dissipative force vanishes, and each nonvanishing motive force becomes conservative, so that the motive work it does per particle around every closed loop in the system vanishes and cannot drive any particle flux.

    1. R.C. Tolman, "The principle of microscopic reversibility," Proc. Nat. Acad. Sci. USA (phys.), 11,436-439 (1925).
    2. M.A. Melehy, Physics Essays, 10,287-303, No.2 (1997).

  • A New Look at Thermodynamics, Part 2: Experimental Corroboration and Applications (2000) [Updated 1 decade ago]

    Accounting for the rate of change of the particle thermal momentum in thermodynamics has unified the theory of semiconductor diodes and solar cells. 1 Theory has accurately been corroborated by extensive experimental data reported by some 27 authors in a period exceeding a quarter century. Recently, it has been shown2 that, in the framework of the new thermodynamic theory, the first and second laws require the electrification of nearly all surfaces, membranes, and other interfaces. This result readily explains numerous diversified phenomena in the physical, life, and engineering sciences, such as: the generation of static electricity by rubbing two different insulators against one another, surface tension, capillarity, adhesion, electrical breakdown in insulators, atmospheric electricity, suspension of fog and of the clouds, change-of-phase electricity (including electricity associated with the growth of cancer cells), and the electromagnetic forces that shape tornadoes, and lead to their destructive properties.

    1. M. A. Melehy, "Thermal Momentum in Thermodynamics, Part 1. Nature of Pressure, Equilibrium and Nonequilibrium. and Generalization of the Maxwell-Einstein Diffusion Force," Physics Essays, 10, 287-303, No.2 (1997).
    2. Ibid, "Thermal Momentum in Thermodynamics, Part 2. Interfacial Electrification: A New Consequence of the First and Second Laws," Physics Essays, 11, 430-443, No.3 (1998).

  • Interfacial Thermodynamics: A General Review (1999) [Updated 1 decade ago]
    by Mahmoud A. Melehy   read the paper:

    Thermal motion involves significant particle momenta p. Incorporating p into thermodynamics leads to a generalization of the Maxwell-Einstein diffusion force. which is highly significant at interfaces. Determining how this force interacts with electric fields1 has led to new, general consequences: (1) Unification of the theory of conduction in diodes and solar cells. Theory has accurately agreed with extensive experimental data reported by some 27 authors, in the period 195-1978. (2) Revealing that the first and second laws2 require a new, important, universal property: the electrification of interfaces. This paper reviews the basic foundation of this novel thermodynamic formulation, and proceeds to explain numerous consequent phenomena and pictures of experimental observations that confirm this thermodynamically-required property of electrification of surfaces, membranes. and other interfaces.

    1. M.A. Melehy. "Thermal Momentum in Thermodynamics. Part I: Nature of Pressure. Equilibrium and Nonequilibrium. and Generalization of the Maxwell?Einstein Diffusion Force." Physics Essays. 10.278?303 (1997).
    2. Ibid. Part 2: "Interfacial Electrification: A New Consequence of thc First and Second Laws," Physics Essays. 11.430-443 (1998.

  • Can the Existence of Electricity be Required by the Thermodynamic Laws? (1998) [Updated 7 years ago]

    Electrodynamics underlies special relativity, and electricity underlies electrodynamics. This paper shows, however, that the first and second laws of thermodynamics in fact, require the existence of electricity in nature. This interesting result can only be arrived at if the time rate of change of the particle thermal momentum is incorporated in thermodynamics, and the consequences are worked out. The outcome will be the novel thermodynamic formulation of generalized fields (TFGF). The TFGF allows calculating at equilibrium the change in entropy, (delta)s, per particle, across any interface, by a new method based on the first and second laws. But (delta)s can be calculated by classical methods. Equating the two values of (delta)s leads to a novel result: under conditions satisfied at almost all surfaces. membranes and other interfaces, there have to exist at such sites forces involving action-at-a-distance and other properties uniquely characteristic of electricity. This basic result explains many mysterious phenomena in nature and others previously explained by resorting to hypotheses ad hoc.


  • Thermal Momentum in Thermodynamics, Part I, Rationale with Examples (1997) [Updated 1 decade ago]

    Thermodynamics, as generally known today, evolved in the 1870's. Fundamental in that important discipline is the concept of pressure. For, all other thermodynamic quantities are related to it. Even the conditions of equilibrium involve that concept. For example, in the case of an isothermal liquid-vapor system in equilibrium, the pressure is assumed to be uniform across the interface. But which pressure is it, the external one, p, measurable with a manometer, or the internal one, P. which reflects the time-rate of change of the thermal momenta of the particles. The magnitude of such a pressure is vastly different from that of p? The classical formulation assumes that the thermodynamically-relevant pressure is p. Otherwise, as it seems at first glance, mechanical equilibrium would not occur.

    But are mechanical and thermodynamic equilibria identical? And is the external pressure thermodynamically relevant? To be invoked is an important premise, which evolved some 50 years after pressure and equilibrium had been defined: the principle of detailed balancing, which characterizes equilibrium in its most general form. This paper shows that it is a direct consequence of that principle that the thermodynamically-relevant pressure is indeed the internal, rather than the external pressure. This result leads to a generalization of the Maxwell-Einstein diffusion force, fD' which is highly significant at interfaces. But such a force is motive, and its properties are drastically different from those of dissipative forces.

    By an example, it is shown that the interaction of motive and dissipative forces in a system is governed by the principle of conservation of energy. An important conclusion will then be shown: mechanical and thermodynamic equilibria are very different from one another, even though one cannot be satisfied without satisfying the other. Theoretical predictions of the present and classical thermodynamic formulations, applied to diodes and solar cells, will be compared with extensive experiments that were reported by some 27 authors, over a period exceeding a quarter of a century. The experiments were conducted in the temperature range of 4.2-800?K. Current variations in some cases varied over a range whose maximum to minimum ratio exceeded 10lD. Results of the present thermodynamic formulation depart drastically from those of the classical formulation, but have accurately agreed with experiment.


  • Thermal Momentum in Thermodynamics, Part II Formulation (1997) [Updated 7 years ago]

    Forces acting on particles in a thermodynamic system may be diffusive, electric, electromagnetic or gravitationaL It is shown here that, regardless of their nature, such forces can either be motive, or dissipative. Near equilibrium, dissipative forces are locally proportional to the particle flux densities, and lead to Ohm's law, Flick's law, and other dispositive laws, and the Einstein diffusion-mobility/viscosity relation. But particle flux densities are locally indeterminate from motive forces. The interaction of all motive and dispositive forces is governed by a fundamental global relation: the law of conservation of energy, as applied to the entire system. This interaction of all motive and dispositive forces in a system is expressed sufficiently close to equilibrium. It will be shown that at equilibrium, each identifiable, dispositive force, and its corresponding particle flux vanish, and each identifiable motive field, likewise, falls into a state of self-balancing. For, each such force becomes conservative, and the work it does per particle vanishes around every possible closed loop in the system, and, consequently, cannot drive any particle flux. In effect, therefore, at equilibrium, not only the balancing occurs for each constituent, as is the case in classical thermodynamics, but also by each identifiable process. This basic result has interesting ramifications concerning the possible explanation of some mysterious interfacial phenomena to be cited.


  • How Detailed Can the Balancing Be at Thermal Equilibrium? (1996) [Updated 1 decade ago]

  • A Second Look at Thermodynamics (1995) [Updated 1 decade ago]

  • Antisymmetrical Cosmology (1995) [Updated 1 decade ago]

  • Thermal Momentum in Component Thermodynamics (1994) [Updated 1 decade ago]

  • Component Thermodynamics and the Existence of Electricity (1994) [Updated 1 decade ago]

  • On the Theory of Generalized Fields in Nonequilibrium Thermodynamics: I) Some General Aspects of the Steady State; II) Unified Theory of Electrical Conduction in p-n Junctions, Heterojunctions and Schottky Diodes (1969) [Updated 7 years ago]

    In Proceedings of the 1969 Pittsburgh International Symposium on "A Critical Review of Thermodynamics", E. B. Stuart et al, eds., Baltimore: Mono Book Corp. (1970), pp. 345-405.