Relevant bibliographies by topics / Thermodynamic Equilibrium Calculations

Academic literature on the topic 'Thermodynamic Equilibrium Calculations'

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Published: 25 May 2024

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Journal articles on the topic "Thermodynamic Equilibrium Calculations"

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Zhang, Tao, and Shuyu Sun. "Thermodynamics-Informed Neural Network (TINN) for Phase Equilibrium Calculations Considering Capillary Pressure." Energies 14, no. 22 (November 18, 2021): 7724. http://dx.doi.org/10.3390/en14227724.

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The thermodynamic properties of fluid mixtures play a crucial role in designing physically meaningful models and robust algorithms for simulating multi-component multi-phase flow in subsurface, which is needed for many subsurface applications. In this context, the equation-of-state-based flash calculation used to predict the equilibrium properties of each phase for a given fluid mixture going through phase splitting is a crucial component, and often a bottleneck, of multi-phase flow simulations. In this paper, a capillarity-wise Thermodynamics-Informed Neural Network is developed for the first time to propose a fast, accurate and robust approach calculating phase equilibrium properties for unconventional reservoirs. The trained model performs well in both phase stability tests and phase splitting calculations in a large range of reservoir conditions, which enables further multi-component multi-phase flow simulations with a strong thermodynamic basis.
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Sundman, Bo, and John Ågren. "Computer Applications in the Development of Steels." MRS Bulletin 24, no. 4 (April 1999): 32–36. http://dx.doi.org/10.1557/s0883769400052167.

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Despite the fact that thermodynamic calculations, strictly speaking, apply only to equilibrium, they may of ten be used in nonequilibrium situations. If one or several of the stable phases are suppressed in the calculations, we have a metastable equilibrium, which is often of practical interest. For example, one may calculate the driving force available to form the more stable phases and model nucleation.Thermodynamic calculations may be performed stepwise to predict microseg-regation during solidification by a Scheil-type calculation (no diffusion in the solid State, infinite diffusion in the liquid, and equilibrium at the interface). In such a calculation, no information other than the thermodynamic properties of the System is used.A more ambitious approach is to com-bine the thermodynamic calculations with kinetic modeis (e.g., diffusion calculations) and thereby predict the rate of reactions. This approach is extremely powerful and may be used to simulate a wide range of different phenomena, including precipitation, homogenization, and diffusional interactionsbetween Substrate and coating.It is usually assumed that thermodynamic equilibrium holds locally at the migrating phase interface between two phases, and the rate of transformation is calculated at each instant by solving a set of flux-balance equations. The fluxes are obtained from a numerical Solution of the multicomponent diffusion equations (see Reference 3).
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Belov, G. V. "Calculation of Equilibrium Composition of Complex Thermodynamic Systems using Julia Language and Ipopt Library." Herald of the Bauman Moscow State Technical University. Series Instrument Engineering, no. 3 (136) (September 2021): 24–45. http://dx.doi.org/10.18698/0236-3933-2021-3-24-45.

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The article considers the possibility of using the Ipopt optimization package for the calculating the phase and equilibrium compositions of a multicomponent heterogeneous thermodynamic system. Two functions are presented for calculating the equilibrium composition and properties of complex thermodynamic systems, written in the Julia programming language. These functions are the key ones in the program integrated with the IVTANTERMO database on thermodynamic properties of individual substances and used for conducting test calculations. The test calculations showed that Ipopt package allows determining the phase and chemical compositions of simple and complex thermodynamic systems with a fairly high speed. Using the JuMP modeling language significantly simplifies the preparation of the initial data for the Ipopt package, therefore the functions presented in this article are very compact. It is shown how the Ipopt package can be used when the temperature of the thermodynamic system is unknown. The approach proposed in this work is applicable both for analyzing the equilibrium of individual chemical reactions and for calculating the equilibrium composition of complex chemically reacting systems. The simplicity of the proposed functions allows their easy integrating into application programs, embedding them into more complex applications, using them in combination with more complex models (real gas, nonideal solutions, constrained equilibria), and, if necessary, modifying them. It should be noted that the versatility of the JuMP modeling language makes it possible to replace the Ipopt package with another one without significant modification of the program text
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Ewing, Mark E., and Daron A. Isaac. "Thermodynamic Property Calculations for Equilibrium Mixtures." Journal of Thermophysics and Heat Transfer 32, no. 1 (January 2018): 118–28. http://dx.doi.org/10.2514/1.t5144.

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Lothenbach, Barbara. "Thermodynamic equilibrium calculations in cementitious systems." Materials and Structures 43, no. 10 (April 17, 2010): 1413–33. http://dx.doi.org/10.1617/s11527-010-9592-x.

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Földényi, Rita, and Aurél Marton. "Organisation of the Analytical, Stoichiometric, and Thermodynamic Information for water Chemistry Calculations." Hungarian Journal of Industry and Chemistry 43, no. 1 (June 1, 2015): 33–38. http://dx.doi.org/10.1515/hjic-2015-0006.

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Abstract A common feature of the chemical processes of the hydrosphere and water treatment plants is that essentially the same types of chemical equilibrium reactions occur in both fields. These equilibria could be acid/base, complexation, redox, precipitation, and interfacial processes. Since these reactions may also occur in combination, the aqueous environments are unavoidably multispecies systems. Due to multiple equilibria, the state of aggregation, the state of oxidation, as well as the electric charge of the species may change dramatically. Calculation of the equilibrium concentration of the species is facilitated by the availability of analytical, stoichiometric, and thermodynamic information that are consistently organised into an ASTI matrix. The matrix makes it possible to apply a uniform algebraic treatment for all occurring equilibria even, if later on, further reactions have to be included in the chemical model. The use of the ASTI matrix enables us to set up the necessary mass balance equations and equilibrium relationships, which together form a non-linear system of equations (NLSE). The goal of our paper is to show that the use of the ASTI matrix approach in cooperation with the powerful engineering calculation software, MATHCAD14, results in fast and easy handling of the NLSE-s and, consequently, the calculations of speciation in aqueous systems. The paper demonstrates the method of application in three examples: the calculation of the pH dependence of the solubility of calcite in closed and open systems, the calculation of the pH and pε in a system where acid/base reactions, complexation equilibria, and redox equilibria occur, and a study of adsorption of lead ions on aluminium oxide.
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Ramette, Richard W. "REACT: Exploring Practical Thermodynamic and Equilibrium Calculations." Journal of Chemical Education 72, no. 3 (March 1995): 240. http://dx.doi.org/10.1021/ed072p240.

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Novák, Josef P., Vlastimil Růžička, Jaroslav Matouš, and Jiří Pick. "Liquid-liquid equilibrium. Computation of liquid-liquid equilibrium in terms of an equation of state." Collection of Czechoslovak Chemical Communications 51, no. 7 (1986): 1382–92. http://dx.doi.org/10.1135/cccc19861382.

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An algorithm for calculating the boiling point pressure at a chosen temperature and composition was used for computing liquid-liquid equilibrium. A lot of attention is paid to the determination of the first approximation which is specified in terms of the conditions of thermodynamic stability. The conditions of thermodynamic stability make as well possible to localize the lower and upper critical end points (LCEP and UCEP. The Redlich-Kwong-Soave equation of state was applied in calculations, and it was found out that this equation with zero interaction parameters predicts well the lower and upper critical end temperatures in the systems methane-n-hexane, ethane-n-eicosane and ethane-n-docosane.
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Pelton, A. D. "Thermodynamic databases and equilibrium calculations in metallurgical processes." Pure and Applied Chemistry 69, no. 5 (January 1, 1997): 969–78. http://dx.doi.org/10.1351/pac199769050969.

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Ze-Qing, Wu, Han Guo-Xing, and Pang Jin-Qiao. "Opacity Calculations for Non-Local Thermodynamic Equilibrium Mixtures." Chinese Physics Letters 19, no. 4 (March 26, 2002): 518–20. http://dx.doi.org/10.1088/0256-307x/19/4/321.

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Dissertations / Theses on the topic "Thermodynamic Equilibrium Calculations"

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Qu, Jingang. "Acceleration of Numerical Simulations with Deep Learning : Application to Thermodynamic Equilibrium Calculations." Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS530.pdf.

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Les simulations numériques sont un outil puissant pour analyser les systèmes dynamiques, mais peuvent être coûteuses en termes de calcul et prendre beaucoup de temps pour les systèmes complexes à haute résolution. Au cours des dernières décennies, les chercheurs se sont efforcés d'accélérer les simulations numériques grâce à des améliorations algorithmiques et au calcul haute performance (HPC). Plus récemment, l'intelligence artificielle (IA) pour la science est en plein essor et implique l'utilisation de techniques d'IA, spécifiquement l'apprentissage automatique et l'apprentissage profond, pour résoudre des problèmes scientifiques et accélérer les simulations numériques, ayant le potentiel de révolutionner un large éventail de domaines. L'objectif principal de cette thèse est d'accélérer les calculs d'équilibre thermodynamique au moyen de techniques utilisées pour accélérer les simulations numériques. Les calculs d'équilibre thermodynamique sont capables d'identifier les phases des mélanges et leurs compositions à l'équilibre et jouent un rôle crucial dans de nombreux domaines, tels que le génie chimique et l'industrie pétrolière. Nous atteignons cet objectif sous deux aspects. D'une part, nous utilisons des cadres d'apprentissage profond pour réécrire et vectoriser les algorithmes impliqués dans les calculs d'équilibre thermodynamique, facilitant l'utilisation de matériel divers pour le HPC. D'autre part, nous utilisons des réseaux neuronaux pour remplacer les sous-routines longues et répétitives des calculs d'équilibre thermodynamique, ce qui est une technique largement adoptée de l'IA pour la science. Un autre point central de cette thèse est de relever le défi de la généralisation de domaine (DG) dans la classification d'images. La DG implique l'entraînement de modèles sur des domaines connus qui peuvent efficacement se généraliser à des domaines inconnus, ce qui est crucial pour le déploiement de modèles dans des applications réelles critiques pour la sécurité. La DG est un domaine de recherche actif en apprentissage profond. Bien que diverses méthodes DG aient été proposées, elles nécessitent généralement des étiquettes de domaine et manquent d'interprétabilité. Par conséquent, nous visons à développer un nouvel algorithme DG qui ne nécessite pas d'étiquettes de domaine et est plus interprétable
Numerical simulations are a powerful tool for analyzing dynamic systems, but can be computationally expensive and time-consuming for complex systems with high resolution. Over the past decades, researchers have been striving to accelerate numerical simulations through algorithmic improvements and high-performance computing (HPC). More recently, artificial intelligence (AI) for science is on the rise and involves using AI techniques, specifically machine learning and deep learning, to solve scientific problems and accelerate numerical simulations, having the potential to revolutionize a wide range of fields. The primary goal of this thesis is to speed up thermodynamic equilibrium calculations by means of techniques used to accelerate numerical simulations. Thermodynamic equilibrium calculations are able to identify the phases of mixtures and their compositions at equilibrium and play a pivotal role in many fields, such as chemical engineering and petroleum industry. We achieve this goal from two aspects. One the one hand, we use deep learning frameworks to rewrite and vectorize algorithms involved in thermodynamic equilibrium calculations, facilitating the use of diverse hardware for HPC. On the other hand, we use neural networks to replace time-consuming and repetitive subroutines of thermodynamic equilibrium calculations, which is a widely adopted technique of AI for science. Another focus of this thesis is to address the challenge of domain generalization (DG) in image classification. DG involves training models on known domains that can effectively generalize to unseen domains, which is crucial for deploying models in safety-critical real-world applications. DG is an active area of research in deep learning. Although various DG methods have been proposed, they typically require domain labels and lack interpretability. Therefore, we aim to develop a novel DG algorithm that does not require domain labels and is more interpretable
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Zinser, Alexander [Verfasser], Kai [Gutachter] Sundmacher, and Achim [Gutachter] Kienle. "Dynamic methods for thermodynamic equilibrium calculations in process simulation and process optimization / Alexander Zinser ; Gutachter: Kai Sundmacher, Achim Kienle." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2019. http://d-nb.info/1219937207/34.

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Höglund, Andreas. "Electronic Structure Calculations of Point Defects in Semiconductors." Doctoral thesis, Uppsala universitet, Fysiska institutionen, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7926.

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In this thesis point defects in semiconductors are studied by electronic structure calculations. Results are presented for the stability and equilibrium concentrations of native defects in GaP, InP, InAs, and InSb, for the entire range of doping conditions and stoichiometry. The native defects are also studied on the (110) surfaces of InP, InAs, and InSb. Comparing the relative stability at the surface and in the bulk, it is concluded that the defects have a tendency to migrate to the surface. It is found that the cation vacancy is not stable, but decomposes into an anion antisite-anion vacancy complex. The surface charge accumulation in InAs is explained by complementary intrinsic doping by native defects and extrinsic doping by residual hydrogen. A technical investigation of the supercell treatment of defects is performed, testing existing correction schemes and suggesting a more reliable alternative. It is shown that the defect level of [2VCu-IIICu] in the solarcell-material CuIn1-xGaxSe2 leads to a smaller band gap of the ordered defect γ-phase, which possibly explains why the maximal efficiency for CuIn1-xGaxSe2 has been found for x=0.3 and not for x=0.6, as expected from the band gap of the α-phase. It is found that Zn diffuses via the kick-out mechanism in InP and GaP with activation energies of 1.60 eV and 2.49 eV, respectively. Explanations are found for the tendency of Zn to accumulate at pn-junctions in InP and to why a relatively low fraction of Zn is found on substitutional sites in InP. Finally, it is shown that the equilibrium solubility of dopants in semiconductors can be increased significantly by strategic alloying. This is shown to be due to the local stress in the material, and the solubility in an alloy can in fact be much higher than in either of the constituting elements. The equilibrium solubility of Zn in Ga0.9In0.1P is for example five orders of magnitude larger than in GaP or InP.
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Belsito, Danielle L. "Application of Computational Thermodynamic and Solidification Kinetics to Cold Sprayable Powder Alloy Design." Digital WPI, 2014. https://digitalcommons.wpi.edu/etd-dissertations/28.

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Military aircraft that require high maneuverability, durability, ballistic protection, reparability, and energy efficiency require structural alloys with low density, high toughness, and high strength. Also, repairs to these aircraft demand a production process that has the flexibility to be relatively in-situ with the same high-performance output. Materials produced by the cold spray process, a thermo-mechanical powder consolidation technique, meet many of the requirements. In accordance with President Obama’s 2011 Materials Genome Initiative, the focus of this effort is to design customized aluminum alloy powders which exploit the unique behavior and properties of the materials created by the cold spray process. Analytical and computational models are used to customize microchemistry, thermal conditioning, and solidification behavior of the powders by predicting equilibrium and non-equilibrium microstructure and resulting materials properties and performance. Thermodynamic, kinetic, and solidification models are used, including commercial software packages Thermo-Calc, Pandat™, and JMatPro®, and TC-PRISMA. Predicted powder properties can be used as input into a cold spray process impact model to determine the consolidated materials’ properties. Mechanical properties of powder particles are predicted as a function of powder particle diameter and are compared to experimental results.
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Lundholm, Karin. "Fate of Cu, Cr, As and some other trace elements during combustion of recovered waste fuels." Doctoral thesis, Umeå : Department of Applied Physics and Electronics, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1132.

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Bratberg, Johan. "Phase equilibria and thermodynamic properties of high-alloy tool steels : theoretical and experimental approach." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-453.

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Yamada, Ryo. "Application of Steepest-Entropy-Ascent Quantum Thermodynamics to Solid-State Phenomena." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/85866.

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Steepest-entropy-ascent quantum thermodynamics (SEAQT) is a mathematical and theoretical framework for intrinsic quantum thermodynamics (IQT), a unified theory of quantum mechanics and thermodynamics. In the theoretical framework, entropy is viewed as a measure of energy load sharing among available energy eigenlevels, and a unique relaxation path of a system from an initial non-equilibrium state to a stable equilibrium is determined from the greatest entropy generation viewpoint. The SEAQT modeling has seen a great development recently. However, the applications have mainly focused on gas phases, where a simple energy eigenstructure (a set of energy eigenlevels) can be constructed from appropriate quantum models by assuming that gas-particles behave independently. The focus of this research is to extend the applicability to solid phases, where interactions between constituent particles play a definitive role in their properties so that an energy eigenstructure becomes quite complicated and intractable from quantum models. To cope with the problem, a highly simplified energy eigenstructure (so-called ``pseudo-eigenstructure") of a condensed matter is constructed using a reduced-order method, where quantum models are replaced by typical solid-state models. The details of the approach are given and the method is applied to make kinetic predictions in various solid-state phenomena: the thermal expansion of silver, the magnetization of iron, and the continuous/discontinuous phase separation and ordering in binary alloys where a pseudo-eigenstructure is constructed using atomic/spin coupled oscillators or a mean-field approximation. In each application, the reliability of the approach is confirmed and the time-evolution processes are tracked from different initial states under varying conditions (including interactions with a heat reservoir and external magnetic field) using the SEAQT equation of motion derived for each specific application. Specifically, the SEAQT framework with a pseudo-eigenstructure successfully predicts: (i) lattice relaxations in any temperature range while accounting explicitly for anharmonic effects, (ii) low-temperature spin relaxations with fundamental descriptions of non-equilibrium temperature and magnetic field strength, and (iii) continuous and discontinuous mechanisms as well as concurrent ordering and phase separation mechanisms during the decomposition of solid-solutions.
Ph. D.
Many engineering materials have physical and chemical properties that change with time. The tendency of materials to change is quantified by the field of thermodynamics. The first and second laws of thermodynamics establish conditions under which a material has no tendency to change; these conditions are called equilibrium states. When a material is not in an equilibrium state, it is able to change spontaneously. Classical thermodynamics reliably identifies whether a material is susceptible to change, but it is incapable of predicting how change will take place or how fast it will occur. These are kinetic questions that fall outside the purview of thermodynamics. A relatively new theoretical treatment developed by Hatsopoulos, Gyftopoulos, Beretta and others over the past forty years extends classical thermodynamics into the kinetic realm. This framework, called steepest-entropy-ascent quantum thermodynamics (SEAQT), combines the tools of thermodynamics with quantum mechanics through a postulated equation of motion. Solving the equation of motion provides a kinetic description of the path a material will take as it changes from a non-equilibrium state to stable equilibrium. To date, the SEAQT framework has been applied primarily to systems of gases. In this dissertation, solid-state models are employed to extend the SEAQT approach to solid materials. The SEAQT framework is used to predict the thermal expansion of silver, the magnetization of iron, and the kinetics of atomic clustering and ordering in binary solid-solutions as a function of time or temperature. The model makes it possible to predict a unique kinetic path from any arbitrary, non-equilibrium, initial state to a stable equilibrium state. In each application, the approach is tested against experimental data. In addition to reproducing the qualitative kinetic trends in the cases considered, the SEAQT framework shows promise for modeling the behavior of materials far from equilibrium.
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Davie, Stuart James. "Relative Free Energies from Non-Equilibrium Simulations: Application to Changes in Density." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/365922.

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Knowledge of free-energy differences for states of a system provides an essential component in understanding many processes, including solubility, reaction rates, and phase changes. Therefore, the development of efficient, accurate free-energy calculation routines has long been of interest within the field of molecular modelling. Until recently, thermodynamic integration, free-energy perturbation and slow-change techniques were the only approaches available for the calculation of free-energy differences between two states of a system. However, with the discovery of non-equilibrium free-energy relations in the late nineties, new calculation approaches are now possible. This thesis demonstrates the application of these new relations by deriving them from statistical mechanical concepts and applying them to a variety of systems. Although other types of systems are considered, the focus of this work is on the investigation of density changes, as the density of a system is one of its fundamental intrinsic properties, and expansion and compression phenomena are central to many thermodynamic investigations. To investigate the convergence properties of the free-energy calculation methods prior to their application to systems undergoing a density change, a novel transformation between Lennard-Jones systems possessing different potentials is developed and simulations are completed for a variety of transformation parameters. In particular, the accuracy of free-energy calculations as a function of transformation rate is considered, along with a detailed analysis of free-energy convergence as a function of the number of transformations completed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical Sciences
Science, Environment, Engineering and Technology
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Razavi, Seyed Mostafa. "OPTIMIZATION OF A TRANSFERABLE SHIFTED FORCE FIELD FOR INTERFACES AND INHOMOGENEOUS FLUIDS USING THERMODYNAMIC INTEGRATION." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1481881698375321.

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Maghsoodloobabakhani, Saheb. "Cristallisation à l'équilibre et hors équilibre d'hydrates mixtes de gaz : Mesures PVTx et modélisation thermodynamique." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEM027.

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Dans ce travail, afin d'étudier la formation à l’équilibre et hors équilibre des hydrates mixtes de gaz, deux procédures de formation, rapide et lente, ont été appliqué à des mélanges de CH4-C2H6-C3H8-nC4H10-CO2-N2. L'objectif de ces deux procédures est d'examiner les effets cinétiques de la vitesse de cristallisation sur l'état final, soit dans des conditions dynamiques habituelles (formation rapide) soit en régime permanent (formation lente). Contrairement à la plupart des données de la littérature, qui fournissent uniquement des données de température-pression-composition gaz (PTy), cette étude fournit également la composition, le volume, la capacité de stockage, la densité de la phase hydrate, ou encore le nombre d'hydratation et la conversion d'eau. Les résultats montrent que, lors d'une cristallisation rapide, le volume d'hydrate augmente de 2% à 69% selon le mélange gazeux. De plus, la capacité de stockage diminue avec l'augmentation de la vitesse de cristallisation. En outre, un modèle thermodynamique, basé sur la méthode classique de van der Waals et Platteuw avec le potentiel de Kihara, a été utilisé. Un nouvel ensemble de paramètres Kihara pour le propane, basé sur une cristallisation lente, a été obtenu avec succès et comparé à la littérature. Les données sur la phase hydrates étant rares dans la littérature, ces dernières ont été collectées, et comparé au modèle thermodynamique précédent. Cela permet de mettre en évidence la capacité de la simulation à prédire la composition de la phase hydrate. Bien que ces outils soient intéressants pour prédire les équilibres de phase des molécules légères, ils deviennent moins fiables lorsque des transitions de phase se produisent (coexistence de structures) ou lorsque des molécules plus lourdes sont impliquées. Une analyse par spectroscopie RAMAN a d’ailleurs mis en évidence la coexistence de structures I et II pour un gaz riche en CO2 à partir d’un mélange CO2/C3H8. Pour conclure, la vitesse de cristallisation influence significativement le procédé de formation d’un hydrate mixte. L’utilisation d’un flash thermodynamique, combinant thermodynamique et bilan de masse, montre bien qu’une cristallisation lente est nécessaire pour satisfaire l’équilibre thermodynamique, et donc augmenter la capacité de stockage, et optimiser les procédés hydrate
In this work, in order to investigate the non-equilibrium behaviors of mixed clathrate hydrates, vapor-liquid-hydrate phase equilibria of mixed gas hydrates from CH4-C2H6-C3H8-nC4H10-CO2-N2 are studied. Two different experimental procedures are used: at quick and slow crystallization rates. The aim is to examine the effects of crystallization rate on the final state, either under usual dynamic (quick formation) or steady state conditions (slow formation). Unlike most of the literature data, providing temperature-pressure-vapor composition (PTy) results, this study also furnishes hydrate composition, volume, storage capacity, density, or hydration number and water conversion. At quick crystallization, hydrate volume increases from 2% to 69% according to the gas mixture. Moreover, storage capacity decreases with increasing rate of crystallization. In addition, a thermodynamic model, based on classical van der Waals and Platteuw method and Kihara potential, has been used. A new set of Kihara parameters for propane, based on slow crystallization, has been obtained successfully and compared to the literature.Besides, a review on guest composition in hydrates from experimental results is suggested, based on open literature. Then, the capability of thermodynamic modeling to simulate these rare data has been investigated. While simulation tools are interesting to predict phase equilibria for light molecules, they become less reliable when phase transition occurs in the system, or when heavier molecules are involved. In addition, the use of RAMAN spectroscopy has illustrated phase transition for CO2/C3H8 mixed hydrates under CO2 rich gas conditions.To conclude, the rate of crystallization significantly influences the process of mixed hydrates formation. The use of a thermodynamic flash shows that slow crystallization is necessary to satisfy the thermodynamic equilibrium, and thus increase storage capacity, and optimize hydrate processes
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Books on the topic "Thermodynamic Equilibrium Calculations"

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1940-, Sandler Stanley I., ed. Models for thermodynamic and phase equilibria calculations. New York: Dekker, 1994.

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Gupta, Roop N. Calculations and curve fits of thermodynamic and transport properties for equilibrium air to 30000 K. Hampton, Va: Langley Research Center, 1991.

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N, Gupta Roop, and United States. National Aeronautics and Space Administration. Scientific and Technical Information Program., eds. Calculations and curve fits of thermodynamic and transport properties for equilibrium air to 30 000 K. [Washington, D.C.]: National Aeronautics and Space Administration, Scientific and Technical Information Program, 1991.

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Gordon, Sanford. Computer program for calculation of complex chemical equilibrium compositions and applications. [Cleveland, Ohio]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1996.

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Gordon, Sanford. Computer program for calculation of complex chemical equilibrium compositions and applications. [Washington, D.C.]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1994.

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Gordon, Sanford. Computer program for calculation of complex chemical equilibrium compositions and applications. Washington, D.C: NASA, 1994.

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A, Reno Martin, Gordon Sanford, and United States. National Aeronautics and Space Administration. Scientific and Technical Information Program., eds. CET93 and CETPC: An interim updated version of the NASA Lewis computer program for calculating complex chemical equilibria with applications. [Washington, DC]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1994.

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Calculations and curve fits of thermodynamic and transport properties for equilibrium air to 30 000 K. Washington, D.C: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1991.

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Currier, Robert Patrick. A statistical mechanical group contribution method for calculating thermodynamic properties of fluids. 1987.

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Electrical Installation Calculations: For Compliance with BS 7671. Blackwell Science Inc, 1998.

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Book chapters on the topic "Thermodynamic Equilibrium Calculations"

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Chen, Long-Qing. "Thermodynamic Calculations of Materials Processes." In Thermodynamic Equilibrium and Stability of Materials, 175–239. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-13-8691-6_8.

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Stateva, Roumiana P., and Georgi St Cholakov. "Challenges in the Modeling of Thermodynamic Properties and Phase Equilibrium Calculations for Biofuels Process Design." In Process Systems Engineering for Biofuels Development, 85–120. Chichester, UK: John Wiley & Sons, Ltd, 2020. http://dx.doi.org/10.1002/9781119582694.ch4.

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Duan, Yu, and Guobin Xu. "Analysis of River Stability in the Middle Reaches of Huaihe River Based on Non-equilibrium Thermodynamicsins." In Lecture Notes in Civil Engineering, 1030–40. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6138-0_91.

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AbstractRiver stability is an important attribute of a river, which includes river pattern stability and river bed stability. The stability of the middle reaches of Huaihe River is one of the important problems concerned by the workers in Huaihe River regulation. The study of the stability of the middle reaches of Huaihe River is of great significance to the river regulation planning and flood prevention and control. To explore the stability of the middle reaches of Huaihe River, the research combined with hydrological data, trying to base on the theory of non-equilibrium thermodynamics system to determine the stability of river pattern, and using the unit stream power calculation formula to analyze the river stability. The research show that, the middle reaches of Huaihe River from Zhengyangguan to Fushan, the river pattern of each section is in a stable state, there is no possibility of conversion in the short time. The variation amplitude of unit stream power in each reach tends to decrease, the natural evolution of the riverbed is also in a stable state. Through the research, the applicability of the river stability analysis method based on the non-equilibrium thermodynamics theory in the Huaihe River is verified, and formed a set of analysis methods suitable for the stability judgment and development evolution trend of the Huaihe River. In this study, the stability of the middle reaches of the Huaihe River was judged theoretically, and the adjustment direction of the river and the evolution trend of the river bed were predicted.
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Bharti, Anand, Debashis Kundu, Dharamashi Rabari, and Tamal Banerjee. "COSMO-SAC: A Predictive Model for Calculating Thermodynamic Properties on a-priori Basis." In Phase Equilibria in Ionic Liquid Facilitated Liquid–Liquid Extractions, 53–90. Boca Raton, FL : CRC Press, Taylor & Francis Group, [2017]: CRC Press, 2017. http://dx.doi.org/10.1201/9781315367163-3.

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Riyahi Malayeri, Kamrooz, Patrik Ölund, and Ulf Sjöblom. "Thermodynamic Calculations Versus Instrumental Analysis of Slag-Steel Equilibria in an ASEA–SKF Ladle Furnace." In Bearing Steel Technologies: 10th Volume, Advances in Steel Technologies for Rolling Bearings, 1–11. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2014. http://dx.doi.org/10.1520/stp158020140025.

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He, Ruoyu, Guangmin Zhao, and Yidong Luo. "Study on the effect of sulfur and silicon dioxide on the reaction of CaO and Na2O with chromium during municipal solid waste incineration based on thermodynamic equilibrium calculation." In Advances in Civil Engineering and Environmental Engineering, Volume 2, 281–86. London: CRC Press, 2023. http://dx.doi.org/10.1201/9781003383031-43.

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Clugston, Michael, Malcolm Stewart, and Fabrice Birembaut. "Chemical Equilibrium." In Making the Transition to University Chemistry. Oxford University Press, 2021. http://dx.doi.org/10.1093/hesc/9780198757153.003.0006.

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This chapter introduces equilibria and equilibrium constants. Equilibrium is recorded when the rate of the forward reaction equates to the rate of the backwards reaction. When equilibrium has been reached, the concentrations of all the substances remain constant. The thermodynamic equilibrium constant is devised when the standard Gibbs energy change is in line with the natural logarithm of the equilibrium constant. The chapter lists the equilibrium calculations mostly used in universities. Le Chatelier's principle refers to the small conditions changes subjected at a system in equilibrium as the equilibrium tends to shift to minimize the effect of the change.
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Atkins, Peter, Julio de Paula, and David Smith. "The origin of thermodynamic properties." In Elements of Physical Chemistry. Oxford University Press, 2016. http://dx.doi.org/10.1093/hesc/9780198727873.003.0072.

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This chapter shows how the molecular partition function is used to calculate and give insight into important thermodynamic functions: internal energy, heat capacity, entropy, and Gibbs energy. It talks about the final step into the calculations of chemically significant expressions when the Gibbs energy is available that shows how equilibrium constants can be calculated from structural and spectroscopic data. It also provides a molecular interpretation of thermodynamic properties that acts as a bridge between spectroscopy and thermodynamics. The chapter reviews how a partition function is used to calculate and interpret thermodynamic properties of systems as small as atoms and as large as biopolymers. It highlights the equilibrium constant, which is related to the distribution of molecules over the available states of a system composed of reactants and products.
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Semeshkin, Vitalii, and Radion Cherkez. "RELATIONSHIP OF NON-EQUILIBRIUM THERMODYNAMICS IN THE HETEROGENEOUS PERMEABLE THERMOELEMENTS." In Science, technology and innovation in the modern world. Publishing House “Baltija Publishing”, 2023. http://dx.doi.org/10.30525/978-9934-26-364-4-1.

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A significant number of thermoelectric processes are described with fundamental law of thermodynamics. This paper describes thermoelectric processes in the permeable thermoelements, which are described with the help of relationships of non-equilibrium thermodynamics. The thermoelectric effects, which are described in this work, are laid in the basis of the work of thermoelectric elements, which make up the modules of generators and coolers. Any thermoelectric module can work in refrigerating regime as well as in generator regime. The difference is that, in order to generate energy and to work in the refrigerating regime, the different temperatures and different semiconductors are optimal, which are used in development of thermoelectric modules. The heterogenous materials, which are used to create new thermoelectric modules, can be defined as materials with different sharp heterogeneity of durability from one phase to the other. This heterogeneity of durability may be caused by microstructure of diversity, heterogeneity of the crystal structure or compositional diversity. The size of phases may be in the range from micrometers to millimeters, the geometry of phases may change and create different material systems. The object of this research is the processes in non-equilibrium thermodynamic systems. The subject of the research is the flow of thermodynamic processes in heterogeneous materials, relationship of non-equilibrium thermodynamics in the heterogeneous permeable thermoelements. The methodology of the research is based on the common scientific methods of analysis and synthesis, induction and deduction, observation and abstraction, which are used to systemize results and calculations of thermoelectric systems. The aim of the work is familiarization with the relationship of non-equilibrium thermodynamics, its systematization and calculation of optimal parameters of permeable thermoelement on its basis. This paper describes the physical nature of thermodynamic and thermoelectric phenomenon, based on the newest actual and classic works of the branch of thermoelectricity, non-equilibrium thermodynamics, applied and thermoelectric material science, and their practical application. The analytical review of the literature about the problematics of non-equilibrium thermodynamics in heterogeneous systems was done. We observed the advantages and disadvantages of these systems. The practical part of this work consists of the calculation of parameters of permeable thermoelement made of thermoelectric material on the base of BismuthTtelluride for thermoelectric cooler or, as it used to say in the field of thermoelectricity, thermoelectric heat pump, calculation of dependence of its parameters on amount and size of channels of permeable thermoelement. While investigating the relationship of non-equilibrium thermodynamics, exactly Gibbs’ equation, Boltzmann’s equation, the equation of coolant and heat flow, equation of cooling coefficient, we systemized them and calculated the optimal parameters for the permeable thermoelectric element of cooling on the base of diverse semiconducting alloy Bi2Te3. On the basis of these calculations, we graphically represented the dependence of parameters of semiconducting permeable thermoelectric element on width of its channel, showed optimal definition of width of channel of permeable thermoelectric element. The results of research showed that, by means of the system of channels with the heat carrier, which make changes in the gradient and the temperature’s distribution on the element, is the significant advantage of the cooling factor of the thermoelectric electric over impenetrable.
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"Chapter 11 | Chemical Equilibrium Calculations." In The ASTM Computer Program for Chemical Thermodynamic and Energy Release Evaluation - Chetah® Version 11.0, 77–84. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2020. http://dx.doi.org/10.1520/ds51hol20200011.

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Conference papers on the topic "Thermodynamic Equilibrium Calculations"

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Hurley, C. D., M. Whiteman, and C. W. Wilson. "The Calculation of Thermodynamic Non Equilibrium Combustion Product Compositions." In ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/99-gt-275.

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A method is presented by which the product composition and temperature of constant pressure combustion reactions can be calculated for non equilibrium conditions, by constraining the products free energy and entropy. The calculations for a hydrogen/ oxygen system are compared with chemical kinetic predictions. From the calculated compositions the relationship between free energy and extent of reaction are derived and thence how the individual product mole fractions vary with extent of reaction. The application of these techniques to modelling combustion chemistry is discussed.
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Zimmer, A. T., and P. Biswas. "336. Thermodynamic Equilibrium Calculations as an Occupational Assessment Tool: Welding Alloy Examples." In AIHce 1998. AIHA, 1999. http://dx.doi.org/10.3320/1.2762736.

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Zhao, Baofeng, Li Sun, Xiaodong Zhang, Lei Chen, Jie Zhang, Guangfan Meng, and Xiangmei Meng. "Thermodynamic Equilibrium Analysis of Rice Husk Pyrolysis." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51052.

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Pyrolysis of biomass materials can implement the efficient conversion of biomass to gaseous, liquid and solid energy products. Compared with experimental research which needs massive apparatus and funds and also takes long time, the computer simulation of biomass pyrolysis is more convenient and flexible to achieve the main characteristics of the process. Simulation of thermodynamic equilibrium for the pyrolysis of rice husk was studied in this paper. Based on the minimization of Gibbs free energy, MATLAB was used to calculate thermodynamic equilibrium for the pyrolysis of rice husk in the temperatures ranges from 523 K to 1723 K at intervals of 100 K. The results showed that the contents of H2 and CO increased rapidly with the temperature from 723 K to 1223 K, while the contents of H2O, CH4, CO2 and C decreased sharply. When the temperature was higher than 1223 K, the yields of H2 and CO reached the maximum of 51 mol% and 48 mol% respectively, and then kept stable. In order to be closer to experimental results, the constrain conditions of element C in tar was introduced in the calculations. The results indicated that, in the main components of tar from 523 K to 1223 K, the contents of naphthalene and toluene both decreased and then toluene vanished gradually. However, the content of benzene increased with increasing temperature and finally became the dominant product when the temperature was above 1300 K.
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Hosokawa, Yoshifumi. "Models for chloride ion bindings in hardened cement paste using thermodynamic equilibrium calculations." In 2nd International RILEM Symposium on Advances in Concrete through Science and Engineering. RILEM Publications, 2006. http://dx.doi.org/10.1617/2351580028.025.

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Paolini, Christopher P., and Subrata Bhattacharjee. "The IGE Model: An Extension of the Ideal Gas Model to Include Chemical Composition as Part of the Equilibrium State." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40762.

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The TEST (The Expert System for Thermodynamics, www.thermofluids.net) web portal is a comprehensive thermodynamic courseware consisting of multimedia problems and examples, an online solution manual for educators, traditional thermodynamic charts and tables, fifteen chapters of animations to illustrate thermodynamic systems and fundamental concepts, and a suite of thermodynamic calculators called daemons for evaluating thermodynamic properties and analyzing thermodynamic problems.. The state module offers Java applets for evaluation of thermodynamic states of different working substances grouped into several material models according to underlying assumptions. Gas mixtures are modeled by the perfect gas (PG) or ideal gas (IG) mixture models. In this work, we extend the IG model mixture model into an ideal gas equilibrium (IGE) mixture model by incorporating chemical equilibrium calculations as part of the state evaluation process. Through a simple graphical interface users can set the atomic composition of a gas mixture. In the state panel, the known thermodynamic properties are entered. For a given pressure and temperature, the mixture’s Gibbs function is minimized subject to atomic constraints and the equilibrium composition along with thermodynamic properties of the mixture are calculated and displayed. What is unique about this approach is that equilibrium computations are performed in the background, without requiring any major change in the familiar user interface used in other state daemons. Properties calculated by this equilibrium state daemon are compared with results from other established applications such as NASA CEA and STANJAN. Also, two different algorithms, an iterative approach and a direct approach based on minimizing different thermodynamic functions in different situation are compared.
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Depraz, Se´bastien, Philippe Rivie`re, Marie-Yvonne Perrin, and Anouar Soufiani. "Band Models for Radiative Transfer in Non-LTE Diatomic Molecules of CO2-N2 Plasmas." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22301.

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A statistical narrow-band model is developed for the optically non-thin electronic systems of carbonaceous molecules in CO2-N2 plasmas and its accuracy is studied under equilibrium and non-equilibrium conditions. Line by line calculations are used to produce curves of growth of transmissivities from which band model parameters are calculated by least-square adjustments. The model is shown to provide quite accurate description of radiative properties and radiative intensities for Doppler, Lorentz, and Voigt line profiles, and for both local thermodynamic equilibrium and a multi-temperature description of the gas mixture thermodynamic state. The model is also suitable for a more general description of the gas thermodynamic state where the electronic state populations are arbitrary.
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Rowe, A., M. Karunaratne, and R. C. Thomson. "NiCoCrAlYHf Coating Evolution through Multiple Refurbishment Processing on a Single Crystal Nickel Superalloy." In AM-EPRI 2013, edited by D. Gandy and J. Shingledecker. ASM International, 2013. http://dx.doi.org/10.31399/asm.cp.am-epri-2013p0412.

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Abstract A combination of creep tests, ex-service blade samples, thermodynamic equilibrium calculations, combined thermodynamic and kinetic calculations, image analysis, chemical composition mapping and heat treatments have been conducted on PWA1483 to determine if microstructural rejuvenation can be achieved when taking the presence of oxidation coatings into account as part of a blade refurbishment strategy. The work has shown that the γ′ morphology changes during creep testing, and that through subsequent heat treatments the γ′ microstructure can be altered to achieve a similar γ′ size and distribution to the original creep test starting condition. Thermodynamic equilibrium calculations have been shown to be helpful in determining the optimum temperatures to be used for the refurbishment heat treatments. The interaction of oxidation resistant coatings with the alloy substrate and refurbishment process have been explored with both experimental measurements and coupled thermodynamic and kinetic calculations. The predictive nature of the coupled thermodynamic and kinetic calculations was evaluated against an ex-service blade sample which had undergone refurbishment and further ageing. In general there was good agreement between the experimental observations and model predictions, and the modelling indicated that there were limited differences expected as a result of two different refurbishment methodologies. However, on closer inspection, there were some discrepancies occurring near the interface location between the coating and the base alloy. This comparison with experimental data provided an opportunity to refine the compositional predictions as a result of both processing methodologies and longer term exposure. The improved model has also been used to consider multiple processing cycles on a sample, and to evaluate the coating degradation between component service intervals and the consequences of rejuvenation of the blade with repeated engine exposure. The results from the experimental work and modelling studies potentially offer an assessment tool when considering a component for refurbishment.
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Kermani, Mohammad J., and Andrew G. Gerber. "Thermodynamic and Aerodynamic Loss Evaluation of Supersonic Nucleating Steam With Shocks." In ASME 2002 Joint U.S.-European Fluids Engineering Division Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/fedsm2002-31087.

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Near saturation steam undergoing rapid expansion is numerically studied in a series of converging diverging nozzles with and without shocks. A detailed examination of the aerodynamic and thermodynamic losses are performed for thermodynamic non-equilibrium conditions. The calculations rely on a new numerical model, previously reported, for non-equilibrium phase change with droplet nucleation. In a systematic approach, the model results are first validated versus experimentally available data and then applied to more general flow situations to assess loss mechanisms. The results indicate that for weak normal shocks situated just downstream of the nozzles throat, the aerodynamic and thermodynamic losses are roughly equivalent. As the back pressure is reduced (i.e. shocks become stronger) the aerodynamic component rapidly becomes the predominant loss mechanism. The thermodynamic loss, associated with heat transfer between the phases, increases only gradually with shock strength. This gradual increase starts from a base level of loss originating with the initial nucleation of moisture, which has a strength and location independent of back pressure.
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Korotkikh, A., and I. Sorokin. "EFFECT OF BORON ON THE COMBUSTION CHARACTERISTICS OF METALLIZED HIGH-ENERGY MATERIALS." In 9TH INTERNATIONAL SYMPOSIUM ON NONEQUILIBRIUM PROCESSES, PLASMA, COMBUSTION, AND ATMOSPHERIC PHENOMENA. TORUS PRESS, 2020. http://dx.doi.org/10.30826/nepcap9a-31.

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The paper presents the results of thermodynamic calculations of the effect of pure boron additives on combustion characteristics of high-energy materials (HEM) based on ammonium perchlorate, ammonium nitrate, active fuel-binder, and powders of aluminum Al, titanium Ti, magnesium Mg, and boron B. The combustion parameters and the equilibrium composition of condensed combustion products (CCPs) of HEM model compositions were obtained with thermodynamic calculation program “Terra.” The compositions of solid propellants with different ratios of metals (Al/B, Ti/B, Mg/B, and Al/Mg/B) were considered. The combustion temperature Tad in a combustion chamber, the vacuum specific impulse J at the nozzle exit, and the mass fraction ma of the CCPs for HEMs were determined.
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Wu, Bei, and Hui Zhang. "Vapor Transport Controlled Process Models for AlN Bulk Sublimation Growth." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56564.

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Sublimation vapor transport method is a widely used technique for the production of optoelectronic materials, such as AlN single crystals. Inductively heated method is most commonly used in high temperature materials processing. In the literature, a one-step reaction with two vapor species, i.e. aluminum (Al) vapor and nitrogen (N2) gas, is usually assumed and a diffusion-controlled growth mechanism is used with thermodynamic equilibrium calculations. In the growth experiments, crystal growth may be in the kinetic controlled region, the interplay between surface kinetics and vapor transport is important. Temperature field with inductively heated method will be simulated in this paper. Afterwards, three growth models are proposed. One model is called the traditional model assuming thermodynamic equilibrium and diffusion as the rate-limiting process, and two other models are developed based on equilibrium partial pressure of either aluminum vapor or reaction nitrogen gas. The predicted growth rates by three models are compared. The advantage and disadvantage of different models are discussed.
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Reports on the topic "Thermodynamic Equilibrium Calculations"

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Kotlar, Anthony J. The Proper Interpretation of the Internal Energy of Formation Used in Thermodynamic Equilibrium Calculations. Fort Belvoir, VA: Defense Technical Information Center, July 1992. http://dx.doi.org/10.21236/ada252369.

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Crowley, David, Yitzhak Hadar, and Yona Chen. Rhizosphere Ecology of Plant-Beneficial Microorganisms. United States Department of Agriculture, February 2000. http://dx.doi.org/10.32747/2000.7695843.bard.

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Rhizoferrin, a siderophore produced by Rhizopus arrhizus, has been shown in previous studies to be an outstanding Fe carrier to plants. However, calculations based on stability constants and thermodynamic equilibrium lead to contradicting conclusions. In this study a kinetic approach was employed to elucidate this apparent contradiction and to determine the behavior of rhizoferrin under conditions representing soil and nutrient solutions. Stability of Fe3+ complexes in nutrient solution, rate of metal exchange with Ca, and rate of Fe extraction by the free ligand were monitored for rhizoferrin and other chelating agents by 55Fe labeling. Ferric complexes of rhizoferrin, desferri-ferrioxamine-B (DFOB), and ethylenediamine-di(o-hydroxyphenylacetic acid) (EDDHA) were found to be stable in nutrient solution at pH 7.5 for 31 days, while ferric complexes of ethylenediaminetetraacetic acid (EDTA) and mugineic acid (MA) lost 50% of the chelated Fe within 2 days. Fe-Ca exchange in Ca solutions at pH 8.7 revealed rhizoferrin to hold Fe at non-equilibrium state for 3-4 weeks at 3.3 mM Ca and for longer periods at lower Ca concentrations. EDTA lost the ferric ion at a faster rate under the same conditions. Fe extraction from freshly prepared Fe-hydroxide at pH 8.7 and with 3.2 mM Ca was slow and followed the order. DFOB > EDDHA > MA > rhizoferrin > EDTA. Based on these results we suggest that a kinetic rather than equilibrium approach should be the basis for predictions of Fe-chelates efficiency. We conclude that the non-equilibrium state of rhizoferrin is of crucial importance for its behavior as a Fe carrier to plants.
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Trowbridge, L. D., and J. M. Leitnaker. SOLGAS refined: A computerized thermodynamic equilibrium calculation tool. Office of Scientific and Technical Information (OSTI), November 1993. http://dx.doi.org/10.2172/10137601.

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Terah, E. I. Practical classes in general chemistry for students of specialties «General Medicine», «Pediatrics», «Dentistry». SIB-Expertise, April 2022. http://dx.doi.org/10.12731/er0556.13042022.

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Videos of 11 practical lessons on general chemistry are presented. The following topics are considered – chemical thermodynamics and kinetics, chemical equilibrium, methods of expressing the concentration of solutions, electrolyte solutions, pH, buffer solutions, hydrolysis, redox pro-cesses. For each topic, the main theoretical provisions are given, as well as a detailed solution of typical calculation problems is given. The total dura-tion of the video lessons is 8 hours 21 minutes.
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Trowbridge, L. D., and J. M. Leitnaker. A spreadsheet-coupled SOLGAS: A computerized thermodynamic equilibrium calculation tool. Revision 1. Office of Scientific and Technical Information (OSTI), July 1995. http://dx.doi.org/10.2172/106516.

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