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Energy and thermodynamic

Mchale J M ef a/1996 Surface energies and thermodynamic stability in nanocrystalline aluminas Science 277 788... [Pg.2920]

The elementary reaction energies and thermodynamics for methanol dehydrogenation have been shown to be significantly influenced by electrode potential. The oxidation pathways become much more favorable at higher potentials. The relative barriers of O—H to C—H bond activation decrease with increasing potential, which decreases the overall selectivity to CO and CO2 and increases the yield of formaldehyde. This is consistent with experimental studies. The oxidation of CO intermediates appears to occur via adsorbed hydroxyl intermediates. The hydroxyl intermediates are more weakly held to the surface than atomic oxygen, and thus have significantly lower barriers for the oxidation of CO. [Pg.124]

The reactive testing laboratories cover fire, dust, kinetics, high energy, and thermodynamics. [Pg.384]

Thermochemistry of cluster compounds. In this short summary of cluster structures and their bonding, a few remarks on their thermochemical behaviour are given, in view of a possible relationship with the intermetallic alloy properties. To this end we remember that for molecular compounds, as for several organic compounds, concepts such as bond energies and their relation to atomization energies and thermodynamic formation functions play an important role in the description of these compounds and their properties. A classical example is given by some binary hydrocarbon compounds. [Pg.293]

The kinetic parameters of Zn(II)/Zn(Hg) electrode reaction in aqueous solution containing perchlorate, nitrate, chloride, and bromide ions were measured at different temperatures (5-50°C) [35]. The Arrhenius activation energy and thermodynamic parameters for the Zn(II)/Zn(Hg) system... [Pg.729]

By comparison, determination of the ionization energies and thermodynamic data for the Sn and Pb dihalides represent classical benchmarks in high temperature photoelectron... [Pg.376]

The National Institute of Standards and Technology s (NIST) Chemical WebBook (webbook.nist.gov/chemistry/) offers free access to ion energy and thermodynamic data for several thousand substances, and is also searchable by chemical substructure. No toxicity or environmental property data are given. [Pg.33]

The elisions that Forbes makes here that deliberately or inadvertently assimilate Watt to nineteenth-century physical science are remarkable and important. Thus the phrase the relations of heat to matter is used to describe the subject of Watt s experiments with the steam engine. For Watt heat is matter, but the phrase assumes its separate identity and easily gives the impression that there is no discontinuity involved between that fact and the beliefs of the author of the invention. It would be too big a stretch for Forbes to assume continuity with Watt when he writes about the work of Carnot, Clapeyron and Thomson, yet even here the rhetoric minimizes the gaps - consider the impact of the key phrase, probably unimagined even by its sagacious author - and encourages the reader to entertain the possibility that Watt did in fact anticipate in some fashion the laws of energy and thermodynamics.23... [Pg.68]

In six experiments the mean A q was 126-0 kcal, and none of the results differed from the mean by more than 2-2 kcal. Lewis and von Elbe deduce from this value together with other accepted dissociation energies and thermodynamic data, Z)(H - OH) = 114 6 ... [Pg.33]

The involvement of thermodynamic figures when the forward electron transfer is the RDS is more subtle and arises because of linear or quadratic [41] relationships between activation free energies and thermodynamic driving force, which applies for outer sphere electron transfers like that in Eq. (41) (Sec. II.C.6). [Pg.19]

McHale JM, Auroux A, Perrotta AJ, Navrotsky A (1997) Surface energies and thermodynamic phase stability in nanocrystalline aluminas. Science 277 788-791 Missana T, Afonso CN, Petford-Long AK, Doole RC (1999) Amorphous-to-nanocrystalline transformation kinetics in SbOx films. Philos Mag A 79 2577-2590... [Pg.55]

McHale JM, Auroux A, Perrotta AJ, Navrotsky A (1997) Surface energies and thermodynamic phase stability in nanocrystalline aluminas. Science 277 788-791 Molteni C, Martonak R, Parrinello M (2001) First principles molecular dynamics simulations of pressure-induced stiuctural transformations in silicon clusters. J Chem Phys 114 5358-5365 Murray CB, Norris DJ, Bawendi MG (1993) Synthesis and characterization of nearly monodisperse CdE (E = S, Se, Te) semiconductor nanocrystallites. J Am Chem Soc 115 8706-8715 Onodera A (1972) Kinetics of polymorphic transitions of cadmium chalcogenides under high pressure. Rev Phys Chem Japan 41 1... [Pg.72]

Owing to their unique physico-chemical properties (solvation, polarity, structure), ILs have been proved to be more than physical solvents, providing an unusual coulombic environment where kinetic constants, activation energies and thermodynamic parameters may be strongly modified with respect to their values in traditional molecular solvents. Indeed, tailored ILs with supplementary functionalities, usually referred to as task-specific ionic liquids (TSILs), can chemically interact with the catalyst, for example acting as an activator, a ligand, etc. [Pg.8]

The possible existence of a set of geometric isomers does not mean that all are seen experimentally. They will differ in strain energy and thermodynamic stability, and as few as a single one may be isolable. [Pg.124]

Assuming negligible conversion between hydromechanical and thermal energies and thermodynamic equilibrium between the fluid and solid phases, the equation for heat transport in porous media can be written (Combamous and Bories 1975) ... [Pg.452]

Isaac Asimov, In the Game of Energy and Thermodynamics You Can t Even Break Even, Smithsonian Institution JournaHime 1970), p. 6 (emphasis added). [Pg.8]

Another important property of thiepine is the equilibrium between thiepine (1) and its valence isomer, benzene episulflde (9). Benzene episuliides are found to be so unstable that they can not be detected hence theoretical treatment should provide helpful information. MNDO molecule force field calculations of the zero point energy, potential energy, and thermodynamic parameters for the valence tautomerization of benzene episulflde (9) and thiepine (1) show that (9) is more stable than (1) both in the gas phase and in polar media (Equation (1)). The equilibrium is shifted towards (1) in polar media. The vapor phase inversion barrier for (1) is 3-5 kJ mol , and is reduced to zero by polar solvents <83MI 903-01 >. [Pg.69]

Lattice energies and thermodynamic parameters have been calculated and tabulated for AlCL and GaCL- ... [Pg.98]


See other pages where Energy and thermodynamic is mentioned: [Pg.96]    [Pg.871]    [Pg.34]    [Pg.545]    [Pg.174]    [Pg.201]    [Pg.39]    [Pg.39]    [Pg.39]    [Pg.39]    [Pg.28]    [Pg.402]    [Pg.102]    [Pg.298]    [Pg.643]    [Pg.101]    [Pg.109]    [Pg.494]    [Pg.283]    [Pg.232]    [Pg.231]    [Pg.23]    [Pg.197]   
See also in sourсe #XX -- [ Pg.109 ]




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Energy Conservation Law and Thermodynamic Systems

Energy and Thermodynamic Relations

Energy and the first law of thermodynamics

Energy changes and first law of thermodynamics

Energy thermodynamics

Energy thermodynamics and

Energy thermodynamics and

Energy, Work, and Heat The First Law of Thermodynamics

Entropy and Free Energy Differences by Calorimetric Thermodynamic Integration

Entropy, Free Energy, and the Second Law of Thermodynamics

Force-field Energies and Thermodynamics

Free energy perturbation and thermodynamic integration methods

Historical Perspective on Metabolic Energy and the Thermodynamics of Phosphate Compounds

Other Thermodynamic Potentials Gibbs and Helmholtz Free Energy

Potential Energy and Molecular Thermodynamics

Relationships Between Gibbs Free Energy and Other Thermodynamic Magnitudes

The PDT and Thermodynamic Integration for Exact Quantum Free Energy Changes

Thermodynamic Fluid Stability and the Gibbs Free Energy

Thermodynamic energy

Thermodynamics Entropy, Free Energy, and the Direction of Chemical Reactions

Thermodynamics and the Free Energy

Thermodynamics and the Free Energy of Chemical

Thermodynamics and the Free Energy of Chemical Substances

Thermodynamics entropy and free energy

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Zero-point Energies and Thermodynamic Corrections

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