THERMODYNAMICS OF SOME SPECIAL FIELDS

1953 ◽  
Vol 31 (2) ◽  
pp. 329-336
Author(s):  
R. V. Krotkov ◽  
A. E. Scheidegger
Keyword(s):  
Free Energy ◽  
Electromagnetic Field ◽  
Internal Energy ◽  
Thermodynamic Functions ◽  
External Electromagnetic Field ◽  
Explicit Formulas ◽  
First Case ◽  
Quantized Fields

The free energy, internal energy, and entropy of two quantized fields are calculated, using the method introduced by Scheidegger and McKay. The two fields examined are those representing (a) an ensemble of mesons bound by an interaction with their source (a nucleon), and (b) an ensemble of electrons perturbed by an external electromagnetic field. The presence of a source in the first case is found to have no effect on the thermodynamic functions of the mesons, while an external electromagnetic field does affect the thermodynamic functions of the electrons. Explicit formulas in the latter case are given.

HETEROGENEOUS DISTRIBUTION OF THE MASSES AS THE SOURCE OF THERMODYNAMIC OSCILLATIONS IN POLYMERS

2003 ◽  
Vol 17 (10) ◽  
pp. 2117-2128
Author(s):  
Lj. MAŠKOVIĆ ◽  
B. S. TOŠIĆ
Keyword(s):  
Free Energy ◽  
Low Temperature ◽  
Internal Energy ◽  
Thermodynamic Functions ◽  
Vibrational Energy ◽  
Thermodynamic Characteristics ◽  
Periodic Functions ◽  
Heterogeneous Distribution ◽  
The Subject ◽  
The Masses

The subject of the study are the thermodynamic characteristics of the phonon gas in the chains with heterogeneous mass distribution. The expressions for the internal energy, entropy and free energy of the system are evaluated both in the region of high and low temperature. It is shown that the mass heterogeneity is the source of the strong dissipation of the vibrational energy, which causes all thermodynamic functions of the chains to be quasi-periodic functions of the temperature.

scholarly journals The Important Thermal Characteristics of Matter and Their Computations with the Use of the Gibbs Potentials

2019 ◽  
Vol 19 (2) ◽  
pp. 134-138
Author(s):  
Y. S. Budzhak ◽  
T. Wacławski
Keyword(s):  
Heat Capacity ◽  
Free Energy ◽  
Specific Heat ◽  
Internal Energy ◽  
Gibbs Free Energy ◽  
Specific Heat Capacity ◽  
Thermodynamic Functions ◽  
Thermodynamic Potential ◽  
Thermal Characteristics ◽  
Dynamic Potential

In this paper, the important thermal characteristics of matter  (they describe thermodynamic systems in a state of thermodynamic equilibrium) were calculated.  There are the following  important thermodynamic functions:   the system   internal energy ,  the thermal function (or enthalpy)   the  free  Helmholtz energy, the thermo-dynamic potential  (or Gibbs free energy), the Gibbs grand thermodynamic potential , the entropy ,  the specific heat capacity . These functions are explicit functions of system’s parameters, they fulfil some mathe-matical relationships  and posses   some total differentials. These  functions  are calculated  in this paper and their physical sense is given in the cited works.

First and second laws of thermodynamics: relationship, “inconsistency”, hidden effects

2020 ◽  
pp. 63-73
Author(s):  
A. M. Savchenko ◽  
Yu. V. Konovalov ◽  
A. V. Laushkin
Keyword(s):  
Free Energy ◽  
Internal Energy ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Entropy Of Mixing ◽  
Ideal Mixing ◽  
Laws Of Thermodynamics ◽  
Relationship Of ◽  
The Relationship

The relationship of the first and second laws of thermodynamics based on their energy nature is considered. It is noted that the processes described by the second law of thermodynamics often take place hidden within the system, which makes it difficult to detect them. Nevertheless, even with ideal mixing, an increase in the internal energy of the system occurs, numerically equal to an increase in free energy. The largest contribution to the change in the value of free energy is made by the entropy of mixing, which has energy significance. The entropy of mixing can do the job, which is confirmed in particular by osmotic processes.

Study of Transcrystallization in Polymer Composites

1989 ◽  
Vol 170 ◽  
Author(s):  
Benjamin S. Hsiao ◽  
J. H. Eric
Keyword(s):  
Thermal Conductivity ◽  
Free Energy ◽  
Carbon Fiber ◽  
Plasma Treatment ◽  
Polymer Composites ◽  
High Performance ◽  
Interfacial Strength ◽  
Fiber Surface ◽  
Semicrystalline Polymers ◽  
First Case

AbstractTranscrystallization of semicrystalline polymers, such as PEEK, PEKK and PPS, in high performance composites has been investigated. It is found that PPDT aramid fiber and pitch-based carbon fiber induce a transcrystalline interphase in all three polymers, whereas in PAN-based carbon fiber and glass fiber systems, transcrystallization occurs only under specific circumstances. Epitaxy is used to explain the surface-induced transcrystalline interphase in the first case. In the latter case, transcrystallization is probably not due to epitaxy, but may be attributed to the thermal conductivity mismatch. Plasma treatment on the fiber surface showed a negligible effect on inducing transcrystallization, implying that surface-free energy was not important. A microdebonding test was adopted to evaluate the interfacial strength between the fiber and matrix. Our preliminary results did not reveal any effect on the fiber/matrix interfacial strength of transcrystallinity.

Studies in the Vulcanization of Rubber. I—Thermochemistry of Vulcanization of Rubber

1930 ◽  
Vol 3 (4) ◽  
pp. 631-639
Author(s):  
John T. Blake
Keyword(s):  
Free Energy ◽  
Internal Energy ◽  
Chemical Reaction ◽  
Effect Of Temperature ◽  
Heat Of Reaction ◽  
Chemical Affinity ◽  
Direct Measure ◽  
Total Change

Abstract WHEN a chemical reaction takes place, it is usually accompanied by an absorption or evolution of heat. The amount of the heat interchange is not a direct measure of the chemical affinity involved in the reaction, nor is it a measure of the free energy of the reaction. The heat of reaction, however, is a measure of the total change in internal energy and is of importance, therefore, in calculating the effect of temperature on a reaction and in elucidating the mechanism of it.

scholarly journals PSEUDOCLASSICAL MODEL OF SPINNING PARTICLE WITH ANOMALOUS MAGNETIC MOMENTUM

1993 ◽  
Vol 08 (05) ◽  
pp. 463-468 ◽  
Author(s):  
D.M. GITMAN ◽  
A.V. SAA
Keyword(s):  
Electromagnetic Field ◽  
External Electromagnetic Field ◽  
Invariant Form ◽  
Pauli Equation ◽  
Spinning Particle ◽  
Dirac Quantization

A generalization of the pseudoclassical action of a spinning particle in the presence of an anomalous magnetic momentum is given. The action is written in reparametrization and supergauge invariant form. The Dirac quantization, based on the Hamiltonian analyzes of the model, leads to the Dirac-Pauli equation for a particle with an anomalous magnetic momentum in an external electromagnetic field. Due to the structure of first class constraints in that case, the Dirac quantization demands for consistency to take into account an operator’s ordering problem.

Electrochemical and thermodynamic properties of U4+ and U3+ on Mo electrode in LiCl-KCl eutectic

2019 ◽  
Vol 107 (2) ◽  
pp. 95-104
Author(s):  
Ru-Shan Lin ◽  
You-Qun Wang ◽  
Zhao-Kai Meng ◽  
Hui Chen ◽  
Yan-Hong Jia ◽  
...  
Keyword(s):  
Free Energy ◽  
Thermodynamic Properties ◽  
Thermodynamic Functions ◽  
Electrochemical Behavior ◽  
Diffusion Coefficients ◽  
Electrochemical Techniques ◽  
Reduction Process ◽  
Standard Potential ◽  
Hcl Gas ◽  
Thermodynamic Functions Of Formation

Abstract In this study, UCl4 was prepared by the reaction of HCl gas with UO2 in the LiCl-KCl eutectic. Then, the electrochemical behavior of U4+ and U3+ on a Mo cathode was investigated by various electrochemical techniques. The reduction process of U4+ was regarded as two steps: U4++e=U3+; U3++3e=U. Diffusion coefficients of U4+ and U3+, the apparent standard potential of U4+/U3+, U3+/U as well as U4+/U in the LiCl-KCl molten salt on the Mo electrode was determined by numerous electrochemical methods. The thermodynamic functions of formation of Gibbs free energy of UCl4 and UCl3 are calculated as well.

scholarly journals Internal volumetric heat generation and heat capacity prediction during a material electromagnetic treatment process using hybrid algorithms

2018 ◽  
Vol 38 (1) ◽  
pp. 74-82
Author(s):  
Edgar García-Morantes ◽  
Iván Amaya-Contreras ◽  
Rodrigo Correa-Cely
Keyword(s):  
Inverse Problem ◽  
Heat Capacity ◽  
Electromagnetic Field ◽  
Heat Generation ◽  
Initial Conditions ◽  
Limited Range ◽  
First Case ◽  
Realistic Situation ◽  
Wide Range ◽  
Volumetric Heat Generation

This work considers the estimation of internal volumetric heat generation, as well as the heat capacity of a solid spherical sample, heated by a homogeneous, time-varying electromagnetic field. To that end, the numerical strategy solves the corresponding inverse problem. Three functional forms (linear, sinusoidal, and exponential) for the electromagnetic field were considered. White Gaussian noise was incorporated into the theoretical temperature profile (i.e. the solution of the direct problem) to simulate a more realistic situation. Temperature was pretended to be read through four sensors. The inverse problem was solved through three different kinds of approach: using a traditional optimizer, using modern techniques, and using a mixture of both. In the first case, we used a traditional, deterministic Levenberg-Marquardt (LM) algorithm. In the second one, we considered three stochastic algorithms: Spiral Optimization Algorithm (SOA), Vortex Search (VS), and Weighted Attraction Method (WAM). In the final case, we proposed a hybrid between LM and the metaheuristics algorithms. Results show that LM converges to the expected solutions only if the initial conditions (IC) are within a limited range. Oppositely, metaheuristics converge in a wide range of IC but exhibit low accuracy. The hybrid approaches converge and improve the accuracy obtained with the metaheuristics. The difference between expected and obtained values, as well as the RMS errors, are reported and compared for all three methods.

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