Two continuing and important objectives of computational chemists and chemical engineers are first, to predict accurately the feasibility and extent of chemical reactions, and second, to predict accurately the rate of approach to chemical equilibrium for ...
National Technical Information Service (NTIS)
... an accurate treatment of the equilibrium structure of the outer layers where ... For likely chemical compositions of extreme Population I, the actual ...
NASA Website
This paper describes the discovery of a chemical equilibrium between silicon fluorides, aluminum fluorides, and HCl that controls the reactivity ratios or stoichiometry of the primary and secondary reactions of HF acid that allows accurate modeling of effluent compositions in laboratory flow tests and is consistent with returns ...
Energy Citations Database
A set of Direct Simulation Monte Carlo (DSMC) chemical-reaction models recently proposed by Bird and based solely on the collision energy and the vibrational energy levels of the species involved is applied to calculate non-equilibrium chemical-reaction rates for atmospheric reactions in hypersonic flows. The DSMC ...
NASA Astrophysics Data System (ADS)
A new time accurate coupled solution procedure for solving the chemical non-equilibrium Navier-Stokes equations over a wide range of Mach numbers is described. The scheme is shown to be very efficient and robust for flows with velocities ranging from M le...
Two continuing and important objectives of computational chemists and chemical engineers are first, to predict accurately the feasibility and extent of chemical reactions, and second, to predict accurately the rate of approach to chemical equilibrium for these reactions. ...
A set of Direct Simulation Monte Carlo (DSMC) chemical-reaction models recently proposed by Bird and based solely on the collision energy and the vibrational energy levels of the species involved is applied to calculate nonequilibrium chemical-reaction rates for atmospheric reactions in hypersonic flows. The DSMC non-equilibrium model ...
Feb 3, 2010 ... The NASA Computer program CEA (Chemical Equilibrium with Applications) calculates Chemical Equilibrium Compositions and properties of ...
Page 1. Chemical Reaction Equilibrium in Nanoporous Materials: ... September 2006 Chemical Reaction Equilibrium in Nanoporous Materials: ...
DTIC Science & Technology
... Descriptors : (*AMINES, ACID BASE EQUILIBRIUM), (*ALKENES, CHEMICAL EQUILIBRIUM), (*PROPANOLS, CHEMICAL EQUILIBRIUM), GASES ...
... Descriptors : (*MOLYBDATES, CHEMICAL EQUILIBRIUM), (*CHEMICAL EQUILIBRIUM, MOLECULAR ASSOCIATION), COMPLEX COMPOUNDS ...
used to obtain chemical equilibrium compositions of complex mixtures with applications to ... The equations describe the conditions for chemical equilibrium ...
Page 1. CHEMICAL EQUILIBRIUM MIXTURE COMPUTATIONS FOR ENERGETIC MATERIAL COMBUSTION IN CLOSED VESSELS ...
This STELLA modeling and writing assignment helps students confront and replace common misconceptions about chemical equilibrium.
NSDL National Science Digital Library
... Title : CALCULATIONS OF CHEMICAL EQUILIBRIUM. IV. DETERMINATION OF SPECIFIC HEAT. Descriptive Note : Journal article,. ...
... ELIMINATING SPECIES IN COMPLEX CHEMICAL EQUILIBRIUM CALCULATIONS ... CHEMICAL EQUILIBRIUM CALCULATIONS NZ Shapiro ...
Recently proposed molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties (i.e., no macroscopic reaction-rate information) are investigated for chemical reactions occurring in upper-atmosphere hypersonic flows. The new models are in good agreement with the ...
PubMed
The method of activation energy asymptotics is used to develop a simple but accurate description of the history of a cold graphite sphere suddenly immersed in a hot oxidizing ambient under conditions such that chemical equilibrium in the gas phase prevails. The conditions for the applicability of the approximate description are ...
Statistical mechanical chemical equilibrium calculations of the properties of high-pressure high-temperature reactive C,H,N,O mixtures are made to derive an accurate self-consistent set of inter-molecular potentials for the product molecules. Previous the...
It has long been known that the problem of determining the equilibrium composition of a solution of chemically reacting species could be formulated as a constrained minimum problem. Previous methods for solving the chemical equilibrium problem in this for...
... Descriptors : (*SYNTHETIC FIBERS, *ACID BASE EQUILIBRIUM), (*FIRE RESISTANT TEXTILES, ACID BASE EQUILIBRIUM), ACRYLIC RESINS ...
Progress in the development of a chemical equilibrium model for hydrothermal brines to 300/sup 0/C is discussed. The model enables accurate solubility predictions to be made for scaling minerals in complex geothermal brine systems (Na-K-Mg-Ca-H-Cl-SO/sub 4/-OH-CO/sub 3/-HCO/sub 3/-CO/sub 2/-H/sub 2/O). The model incorporates a highly ...
Protons generated in chemically amplified resists drive pattern formation reactions such as acid catalytic deprotection reactions. Proton dynamics is controlled by the addition of base quenchers so that ultrafine patterns are obtained. However, the details of interaction between protons and base quenchers are still unclear. In this study, we investigated the reactions of ...
We describe a method for deconvoluting incompletely resolved CARS spectra to obtain quantum state population distributions. No particular form for the rotational and vibrational state distribution is assumed, the population of each quantum state is treated as an independent quantity. This method of analysis differs from previously developed approaches for the deconvolution of CARS spectra, all of ...
... WEIGHT, COMPUTER PROGRAMS, QUADRATIC PROGRAMMING, DETERMINATION, CHEMICAL EQUILIBRIUM, SEDIMENTATION ...
... Descriptors : , (*CHEMICAL EQUILIBRIUM, ORGANIC SOLVENTS), (*ORGANIC SOLVENTS, ACID BASE EQUILIBRIUM), ETHYLENEDIAMINE ...
... Accession Number : AD0706020. Title : COMPUTING EQUILIBRIUM COMPOSITIONS OF IDEAL CHEMICAL SYSTEMS. ...
... METHOD FOR THE CALCULATION OF NON ... EQUILIBRIUM ELECTRON DENSITIES IN HIGH ... CHEMICAL REACTIONS, DENSITY, DISSOCIATION ...
As such, it is accurately described or modeled using the solubility product equilibrium ... As equilibrium processes, both the acid/base equilibrium and solubility ...
Treesearch
Word associations were used to map the conception of high school students concerning the concepts chemical equilibrium and equilibrium. It was found that the preconception of the two concepts was differentiated on noncritical dimensions; equilibrium being associated with everyday life experiences and ...
... Descriptors : *REACTION KINETICS, TABLES(DATA), CHEMICAL EQUILIBRIUM, CHEMICAL REACTIONS, THEORY, MATHEMATICAL ...
We propose a second version of the van der Waals density functional of Dion [Phys. Rev. Lett. 92, 246401 (2004)]10.1103/PhysRevLett.92.246401, employing a more accurate semilocal exchange functional and the use of a large- N asymptote gradient correction in determining the vdW kernel. The predicted binding energy, equilibrium separation, and ...
... OF AIRIN CHEMICAL EQUILIBRIUM SINCLUDING SECOND VIRIAL CORRECTIONS FROM 15000K TO 1510000K ... IN CHEMICAL EQUILIBRIUM ...
... IN CHEMICAL EQUILIBRIUM INCLUDING SECOND VIRIAL CORRECTIONS FROM 20000 K TO 15,0000K By ... IN CHEMICAL EQUILIBRIUM ...
A substantially modified version of the NASA-Lewis Chemical Equilibrium Code was recently developed.
NASA Technical Reports Server (NTRS)
TITLE AND SUBTITLE: Computer Program for Calculation of Complex Chemical Equilibrium Compositions and Applications II. User's Manual and Program ...
... bulk pressure on the reaction equilibrium in ... CARLO METHOD, RESPONSE, COEFFICIENTS, CHEMICAL REACTIONS, PRESSURE, MONOMERS ...
... Accession Number : ADA396193. Title : Chemical Equilibrium Code with Compressibility for Ablation and Erosion Calculations. ...
A rapid computational method has been developed to determine the chemical composition of equilibrium
... Title : A Review of Equation of State Models, Chemical Equilibrium Calculations and CERV Code Requirements for SHS Detonation Modelling. ...
Thermodynamics and physical properties are central to the practice of chemical engineering. This is evident from the fact that 70 to 90% of both investment and energy operating costs in a typical chemical plant involves the separations and purifications equipment which are designed largely on the basis of phase equilibrium. Further, ...
We present new quasi-steady-state (QSS) and partial- equilibrium (PE) methods for integrating systems of ordinary differential equations (ODEs) that arise from chemical reactions. These methods were developed for use in process-split reacting-flow simulations. The new QSS integrator is a second-order predictor- corrector method that is A-stable for linear ...
The objective of our research has been to develop computational methods that have the capability of accurately predicting equilibrium constants of typical organic reactions in gas and liquid solution phases. We have chosen Diels-Alder reactions as prototy...
The thermodynamic conditions characterizing solidification were evaluated by calculating isothermal variations of the chemical potentials of and the effects of pressure on graphite like and sphalerite boron nitride. Heat capacity, enthalpy and entropy were calculated. Least square fit was used to extrapolate the temperature dependence of the potentials. Nucleation and crystal ...
Progress in the development of a chemical equilibrium model for hydrothermal brines to 300 sup 0 C is discussed. The model enables accurate solubility predictions to be made for scaling minerals in complex geothermal brine systems (Na-K-Mg-Ca-H-Cl-SO sub ...
The purpose of this project is the development of a method for calculation of chemical equilibrium in support of Institute of Gas Technology Prime Contract No. 5011-321-0140 with the Gas Research Institute. The thrust of IGT's project is to develop laboratory capability for accurate analysis of brine samples recovered under ...
We present a new method for the prediction of the equilibrium properties of dense gases containing hydrogen isotopes. The proposed approach combines the Feynman-Hibbs effective potential method and a deconvolution scheme introduced by Weeks et al. The resulting equations of state and the chemical potentials as functions of pressure for each of the hydrogen ...
The effects of compressibility, chemical reaction exothermicity and non- equilibrium chemical modeling in a reacting plane mixing layer were investigated by ...
The chemical composition of the SiC deposit is assessed both from the calculated total fluxes of carbon and silicon and from chemical equilibrium ...
Linear stability theory for chemically reacting (equilibrium and nonequilibrium) flows is applied to
... to the chemical stability of ... Descriptors : (*DEHYDRATED FOODS, BIBLIOGRAPHIES), MOISTURE ... Subject Categories : FOOD, FOOD SERVICE ...
Thermodynamic laws, including Gibbs' equation, are reviewed for open systems. Defining chemical equilibrium by the vanishing of the chemical reaction part of entropy generation, the authors show that the condition for chemical equilibrium in open systems ...
catalyst) on the equilibrium state and on the rates of chemical reaction. ... PO 9 Represent the force conditions required to maintain static equilibrium. ...
Phase Equilibriums, Chemical Equilibriums, and Solutions Radiation Chemistry, Photochemistry, and Photographic and Other Reprographic Processes Surface Chemistry and Colloids...
Science.gov Websites
Changes made to the Coal Gasification Project are reported. The program was developed by equilibrium
