The relationship between elasticity and structure of macromolecular networks - Outline of a new approach
Statistical mechanics, chemical analysis, and elasticity studies for macromolecular networks like rubber
Thirion, P.↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Theory of localized and non-localized adsorption.
Gas adsorption on solids, discussing statistical mechanical theory assuming localized adsorption for first adlayer and nonlocalized mobile layer adsorption on top
Kim, S. K.↗
Phonon theory of solid-state diffusion including anharmonic effects.
Lattice vibration theory of solid state diffusion for Cu including anharmonic effects formulated using equilibrium statistical mechanics, considering interacting phonon events
Franklin, W.↗
Themis signal analysis statistics research program. Always usable limited-length sequential permutation tests for two-way ANOVA
Statistical mechanics of always usable, limited length, permutation tests for two way analysis of variance and applications in quality control
Walsh, J. E.↗
Themis signal analysis statistics research program. Generally usable sequential randomization tests for two-way ANOVA that emphasize the more recent data
Statistical mechanics of sequential randomization tests for two way variance emphasizing most recently acquired data and applications in quality control
Walsh, J. E.↗
Themis signal analysis statistics research program. Always applicable sequential randomization tests for one-way ANOVA that emphasize the more recent data
Statistical mechanics of sequential randomization tests for one way variance emphasizing most recently acquired data and applications in quality control
Walsh, J. E.↗
Confidence regions for variance ratios in variance components models
Statistical mechanics for constructing confidence intervals for variance ratios in balanced and unbalanced experimental designs
Al-Barhawe, A. S.↗
A turbulence description of couette flow
Statistical mechanics for wall shear turbulence in couette flow based on Brownian motion and comparison with stochastic theory based on Navier-Stokes equation
Chung, P. M.↗
Astronautics and aeronautics, 1969 Chronology on science, technology, and policy
Statistical mechanics for wall shear turbulence in Couette flow based on Brownian motion and comparison with stochastic theory based on Navier-Stokes equation
Source record↗
A quasi-chemical approach to the thermodynamics of ternary solid solutions containing both substitutional and interstitial solute atoms
Ternary solid solutions with substitutional and interstitial solute atoms, developing statistical mechanical interaction model
Alex, K.↗
Kinetic theory of a two-dimensional magnetized plasma.
Several features of the equilibrium and nonequilibrium statistical mechanics of a two-dimensional plasma in a uniform dc magnetic field are investigated. The charges are assumed to interact only through electrostatic potentials. The problem is considered both with and without the guiding-center approximation. With the guiding-center approximation, an appropriate Liouville equation and BBGKY hierarchy predict no approach to thermal equilibrium for the spatially uniform case. For the spatially nonuniform situation, a guiding-center Vlasov equation is discussed and solved in special cases. For the nonequilibrium, nonguiding-center case, a Boltzmann equation, and a Fokker-Planck equation are derived in the appropriate limits. The latter is more tractable than the former, and can be shown to obey conservation laws and an H-theorem, but contains a divergent integral which must be cut off on physical grounds. Several unsolved problems are posed.
Vahala, G.↗
The closure approximation in the hierarchy equations.
The expectation of the solution process in a stochastic operator equation can be obtained from averaged equations only under very special circumstances. Conditions for validity are given and the significance and validity of the approximation in widely used hierarchy methods and the ?self-consistent field' approximation in nonequilibrium statistical mechanics are clarified. The error at any level of the hierarchy can be given and can be avoided by the use of the iterative method.
Adomian, G.↗
Multidisciplinary research in space sciences and engineering with emphasis on theoretical chemistry
A broad program is reported of research in theoretical chemistry, particularly in molecular quantum and statistical mechanics, directed toward determination of the physical and chemical properties of materials, relation of these macroscopic properties to properties of individual molecules, and determination of the structure and properties of the individual molecules. Abstracts are presented for each research project conducted during the course of the program.
Hirschfelder, J. O.↗
Analysis of energy disposal - Thermodynamic aspects of the entropy deficiency of a product state distribution
A thermodynamic-like approach to the characterization of product state distributions is outlined. A moment analysis of the surprisal and the entropy deficiency is presented from a statistical mechanical viewpoint. The role of reactant state selection is discussed using the 'state function' property of the entropy.
Levine, R. D.↗
A study of turbulent flow between parallel plates by a statistical method
Turbulent Couette flow between parallel plates was studied from a statistical mechanics approach utilizing a model equation, similar to the Boltzmann equation of kinetic theory, which was proposed by Lundgren from the velocity distribution of fluid elements. Solutions to this equation are obtained numerically, employing the discrete ordinate method and finite differences. Two types of boundary conditions on the distribution function are considered, and the results of the calculations are compared to available experimental data. The research establishes that Lundgren's equation provides a very good description of turbulence for the flow situation considered and that it offers an analytical tool for further study of more complex turbulent flows. The present work also indicates that modelling of the boundary conditions is an area where further study is required.
Srinivasan, R.↗
Satellite disintegration dynamics
The subject of satellite disintegration is examined in detail. Elements of the orbits of individual fragments, determined by DOD space surveillance systems, are used to accurately predict the time and place of fragmentation. Dual time independent and time dependent analyses are performed for simulated and real breakups. Methods of statistical mechanics are used to study the evolution of the fragment clouds. The fragments are treated as an ensemble of non-interacting particles. A solution of Liouville's equation is obtained which enables the spatial density to be calculated as a function of position, time and initial velocity distribution.
Dasenbrock, R. R.↗
The 55 K specific heat anomaly in palladium hydride
A specific heat anomaly in PdH and PdD has been observed by Aston et al. (1957) close to 55 K. Its position was found to be independent of hydrogen concentration and its magnitude to be linear in hydrogen concentration. Ferguson's (1965) and Brodowsky's (1972) explanations of the anomaly are shown to be unsatisfactory. This is true also for the detailed mechanical statistical model proposed by Staford and McLellan (1974) for interstitial solid solutions of hydrogen in transition metals. It is shown that Gopal's (1966) simple Schottky model of specific heat anomaly, which considers a system of several levels with Boltzmann statistics, provides much better agreement with experiment than the more elaborate models, both in magnitude and in predicting a linear dependence on hydrogen concentration.
Jacobi, N.↗
Astrodynamics 1975; Conference, Nassau, Bahamas, July 28-30, 1975, Technical Papers
Articles are grouped under four headings: (1) dynamics and control of satellites; (2) satellite mission analysis; (3) Aeros-B and Symphonie satellite engineering problems; (4) optimization and control techniques applied to solar space heating and cooling of buildings. Topics covered include: communications and earth survey satellite systems, a system of two counter-orbiting satellites measuring GRT-predicted nodal drag, statistical mechanics studies of the spatial density function of orbiting space junk, attitude control of satellites, nutation dampers, low thrust inertial guidance and ascent inertial guidance, a shuttle-launched multi-comet intercept mission, preflight and in-flight analysis of the Atmosphere Explorer (AE-C) satellite, and launch-encounter strategy for the Mariner 1977 Jupiter-Saturn mission. Individual items are announced in this issue.
Powers, W. F.↗