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Methods calculation method

Hydrates of natural gases are formed in wells, in elements of the field equipment for gas preparation, and also in gas pipelines at certain values of pressure and temperature determined by the phase diagrams of heterogeneous equilibrium. In practice, in order to determine the conditions for the beginning of hydrate formation, one uses graphic methods, calculation method with use of equilibrium constants, semi-graphical method with the Barrer-Stuart equation, and experimental method. [Pg.667]

Correlation methods, calculation methods, group contribution methods, and theoretical concepts for polymer solubihty parameters are not introduced here. The reader is, for example, referred to [1990KRE1, 2002BIC1, 2007HAN1]. Calculated polymer solubility parameters can also be foimd in [1999BRA1]. Calculated values are not included in the table of Chapter 3.3. [Pg.13]

Unfortunately, good binary data are often not available, and no model, including the modified UNIQUAC equation, is entirely adequate. Therefore, we require a calculation method which allows utilization of some ternary data in the parameter estimation such that the ternary system is well represented. A method toward that end is described in the next section. [Pg.66]

LCAO method A method of calculation of molecular orbitals based upon the concept that the molecular orbital can be expressed as a linear combination of the atomic orbitals. [Pg.236]

The current calculation methods are based on the hypothesis that each mixture whose properties are sought can be characterized by a set of pure components and petroleum fractions of a narrow boiling point range and by a composition expressed in mass fractions. [Pg.86]

This factor is the intermediate parameter employed in numerous calculational methods. For petroleum cuts obtained by distillation from the same crude oil, the Watson factor is generally constant when the boiling points are above 200°C. [Pg.97]

In the first type of method, the density at saturation pressure is calculated, then this density is corrected for pressure. The COSTALD and Rackett methods belong to this category. Correction for pressure is done using Thompson s method. These methods are applicable only if the reduced temperature is less than 0.98. [Pg.114]

The average error of this simplified method is about 3°C and can reach 5°C. Table 4.22 shows an application of this method calculating the temperature of hydrate formation of a refinery gas at 14 bar. Table 4.23 gives an example applied to natural gas at 80 bar. Note that the presence of H2S increases the hydrate formation temperature. [Pg.175]

This calculational method is nevertheless only of limited interest and concerns only certain pure organic products for which direct measurement of the NHVj is difficult owing to a variety of reasons such as cost and availability. [Pg.181]

Calculational methods. Associating the analysis, the knowledge of the property-structure relationships, and the calculation methods has made possible the replacement of costly and arduous test methods by quicker tests whose results are linked by calculations to the characteristic under study. Some examples are the cetane number, in some cases, the octane number, or the characteristics of LPG (refer to Chapter 3). [Pg.296]

Fig. 1 Measuring method of echo height of side drill hole Fig. 2 Calculation Method of Echo Directivity [or SH Wave Probes... Fig. 1 Measuring method of echo height of side drill hole Fig. 2 Calculation Method of Echo Directivity [or SH Wave Probes...
There has been a general updating of the material in all the chapters the treatment of films at the liquid-air and liquid-solid interfaces has been expanded, particularly in the area of contemporary techniques and that of macromolecular films. The scanning microscopies (tunneling and atomic force) now contribute more prominently. The topic of heterogeneous catalysis has been expanded to include the well-studied case of oxidation of carbon monoxide on metals, and there is now more emphasis on the flexible surface, that is, the restructuring of surfaces when adsorption occurs. New calculational methods are discussed. [Pg.802]

Figure Al.3.16. Reflectivity of silicon. The theoretical curve is from an empirical pseudopotential method calculation [25], The experimental curve is from [31],... Figure Al.3.16. Reflectivity of silicon. The theoretical curve is from an empirical pseudopotential method calculation [25], The experimental curve is from [31],...
We assume that the unbinding reaction takes place on a time scale long ( ompared to the relaxation times of all other degrees of freedom of the system, so that the friction coefficient can be considered independent of time. This condition is difficult to satisfy on the time scales achievable in MD simulations. It is, however, the most favorable case for the reconstruction of energy landscapes without the assumption of thermodynamic reversibility, which is central in the majority of established methods for calculating free energies from simulations (McCammon and Harvey, 1987 Elber, 1996) (for applications and discussion of free energy calculation methods see also the chapters by Helms and McCammon, Hermans et al., and Mark et al. in this volume). [Pg.55]

Radmer, R.. 1., Kollman, P. A. Approximate free energy calculation methods and structiire based ligand design. J. Comp. Aid. Mol. Desgn (in press)... [Pg.161]

Here, and Lj are local indices having the form shown in Eq. (5), where lo is a constant characterizing the ith atom (in some cases the atom valence can be used to this end), Nh is the number of attached hydrogen atoms and is the charge density calculated by some fast method such as the Marsili-Gasteiger charge calculation method [7]. [Pg.295]

Obviously, to model these effects simultaneously becomes a very complex task. Hence, most calculation methods treat the effects which are not directly related to the molecular structure as constant. As an important consequence, prediction models are valid only for the system under investigation. A model for the prediction of the acidity constant pfQ in aqueous solutions cannot be applied to the prediction of pKj values in DMSO solutions. Nevertheless, relationships between different systems might also be quantified. Here, Kamlet s concept of solvatochro-mism, which allows the prediction of solvent-dependent properties with respect to both solute and solvent [1], comes to mind. [Pg.488]

D descriptors), the 3D structure, or the molecular surface (3D descriptors) of a structure. Which kind of descriptors should or can be used is primarily dependent on the si2e of the data set to be studied and the required accuracy for example, if a QSPR model is intended to be used for hundreds of thousands of compounds, a somehow reduced accuracy will probably be acceptable for the benefit of short processing times. Chapter 8 gives a detailed introduction to the calculation methods for molecular descriptors. [Pg.490]

Fujita et al. were the first to develop a calculation method that was based, analogously to the Hammett approach, on substituent constants r[6] (see Eq. (7))... [Pg.492]

The complete neglect of differential overlap (CNDO) method is the simplest of the neglect of differential overlap (NDO) methods. This method models valence orbitals only using a minimal basis set of Slater type orbitals. The CNDO method has proven useful for some hydrocarbon results but little else. CNDO is still sometimes used to generate the initial guess for ah initio calculations on hydrocarbons. [Pg.34]


See other pages where Methods calculation method is mentioned: [Pg.907]    [Pg.941]    [Pg.716]    [Pg.650]    [Pg.253]    [Pg.260]    [Pg.440]    [Pg.124]    [Pg.381]    [Pg.21]    [Pg.29]    [Pg.31]    [Pg.33]    [Pg.35]    [Pg.37]    [Pg.39]    [Pg.43]    [Pg.45]    [Pg.47]    [Pg.49]    [Pg.210]    [Pg.213]    [Pg.269]    [Pg.455]    [Pg.114]    [Pg.36]    [Pg.50]    [Pg.102]    [Pg.103]    [Pg.103]   
See also in sourсe #XX -- [ Pg.214 , Pg.215 ]




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AIMD simulation method electronic structure calculations

Ab Initio Methods for the Calculation of Excited States

Additional Methods for Calculating the Entropy

Analysis calculation methods

Analytic Methods for Calculation of Partial Molar Properties

Analytical calculation models versus Finite Element Method (FEM)

Approximate method, for calculating

Approximate methods of field calculation in induction logging

Approximation method, equilibrium constant calculations

Bioavailability calculation methods

Boiling point, normal calculation methods

Boundary element method model calculations

Calculated vs Experimental Chemical Shift Tensors Using Different NMR Methods

Calculation Methods for Constant-Rate Drying Period

Calculation Methods for EPR of the Isolated Ions

Calculation Methods for Falling-Rate Drying Period

Calculation Methods for Multiple-Effect Evaporators

Calculation Methods for Single-Effect Evaporators

Calculation Procedures Based on Different Integral Methods

Calculation method

Calculation methods empirical

Calculation methods for

Calculation of Determinants by the Gauss Method

Calculation of Internal Stresses by the Lattice Cell Method

Calculation of phase diagrams method

Calculation of pressure in dynamic Monte Carlo methods

Calculation of separating stages by the McCabe-Thiele method in batch operation

Calculations analytical methods

Calculations factor-unit method

Calculations graphical methods

Calculations numerical methods

Calculations relativistic methods

Commonly Used Methods for the Calculation of Endpoints

Comparison of Calculated Rates to Other Methods for Polyethylene Films

Comparisons of calculational methods

Composite methods for energy calculations

Computational methods calculations

Computational methods electronic structure calculations

Configuration-interaction methods electronic structure calculations

Counterpoise method, in calculations heterocycles

Critical properties calculation methods

Crystal structure calculation cluster method

Current distribution calculation methods

Density functional theory methods calculations

Density, gases (Con calculation methods

Direct variational methods resonance calculations

Discrete variational methods calculations

Discrete variational methods first-principles calculations

Discussion of Neutronic Calculation Methods

Early Methods of MLP Calculations

Electrophoretic mobility calculation methods

Energies, calculated by ab initio methods

Enthalpy calculation methods

Entropy calculation methods

Equilibrium constant expression approximation method calculations with

Error Sources and Calculational Methods

Extended Hiickel molecular orbital method calculation procedure

Extended Huckel method band calculations

Extraction calculation methods, process fundamentals

Feinberg-Galanin Method of Heterogeneous-reactor Calculation

Finite Volume Method for Calculation of Flow Field

Finite difference calculation method

Finite-difference methods, polarizability calculations

Finite-field method polarizability calculations

Fixed-charge method, polarizability calculations

Flammability limits calculation methods

Flash point calculation methods

Force-field methods, calculation

Force-field methods, calculation of molecular structure and energy

Fragmentation method, calculation

Frechet derivative calculation using finite difference methods

Frechet derivative calculation using the differential method

Free energy calculations linear response method

Free energy calculations methods

Free energy calculations rapid methods, approximate

Free energy calculations simulation methods

Free-energy calculations expanded ensemble methods

GIAO method , chemical shift calculation

Gaussian methods correlated calculations

General Requirements upon the Methods for Calculating Potential Energy Surfaces

Global optimization method calculations

Ground-state dipole moments - calculate semiempirical methods

Hand calculation methods which account for. mass loss

Hartree-Fock method calculations

Hartree-Fock method energy calculations

Hartree-Fock method transition-metal calculations using

Hartree-Fock-Slater method total energy calculations

Heat capacity calculation methods

Horvath-Kawazoe method calculation

Hydrogen calculation methods

IGLO method , chemical shift calculation

Implementation of Kohn-Sham LCAO Method in Crystals Calculations

Integral calculation methods

LAPW method calculations

Lattice energy calculation Monte Carlo methods

Least squares method sample calculation

Liquid/vapor calculation method

MCSCF method, shielding calculations

MO calculations methods

Melting point, normal calculation methods

Method for calculating potential energy surfaces

Method of calculation

Methods and Examples for Large Library Diversity Calculations

Methods for Calculating the Entropy from MC and MD Samples

Methods for Chemical Shift Calculations

Methods molecular mechanics calculations

Methods of electronic structure calculation

Methyl radicals calculation methods

Molecular Rydberg states calculation method

Molecular alternate calculation method

Molecular orbital calculations CNDO methods

Molecular orbital calculations, light method

Molecular structure and energy, calculation of, by force-field methods

Multielectron methods first principles calculations

Neutronics calculation methods

New Methods for Calculating Ecological Risk

Newton-Raphson method equilibrium calculations

Nitrogen dioxide calculation methods

Other methods of calculating thermodynamic changes accompanying growth

Partial ionization cross sections calculation methods

Peak areas calculation methods

Physical Methods and Energy Calculations

Physical Separation Methods and Calculations

Polyatomic Molecules Method of Calculation

Potential energy surfaces, calculation perturbation methods

Practical Methods for Quantized VTST Calculations

Pseudopotential calculation methods

Quantized classical path method calculations

Quantum chemical calculations semiempirical methods

Quantum chemical method/calculation

Quantum defect orbital calculation method

Quantum mechanical methods, calculation

Quantum mechanical methods, calculation widths

Rate Constant Calculation for Thermal Reactions: Methods and Applications, Edited by Herbert

Rate constants, calculating method

Redox potentials, calculations computational methods

Relativistic Methods for Molecular Calculations and Diatomic Gold Compounds

Relativistic methods four-component calculations

Scaling factor, calculation methods

Selection of the Calculation Method

Self-consistent field methods, effective nuclear charge calculated using

Self-consistent held methods calculation

Semi-empirical methods for calculations

Semiempirical methods of electronic structure calculation

Separation operations, multistage calculation methods

Settlement calculation methods

Shielding calculation methods

Shortcut methods from rigorous calculation results

Simple Calculations Using the Hiickel Method

Simplified Calculation Method for Dispersion

Skewing Momenta Distributions to Enhance Free Energy Calculations from Trajectory Space Methods

Slab method, surface calculations

Stability constants calculation methods

Stage calculations computer methods

Surface tension calculation methods

THEORETICAL METHODS CALCULATIONS

Temperature effects calculation methods

Test Method for Calculated Cetane Index by Four Variable Equation

The Charge Balance Calculation Method and Buffers

The Development of Modern Methods to Calculate Reduced Isotopic Partition Function Ratios

The Mole Ratio Method of Stoichiometric Calculations

Theoretical Methods for Free Energy Calculations

Theoretical methods chemical property bonding calculations

Theoretical methods thermodynamic property calculations

Thermal conductivity calculation methods

Tiered calculation method

Vacuum Flow calculation methods

Vapor pressure calculation methods

Variation method calculations

Vibrational frequencies calculations, methods

Viscosity calculation methods

Whole reactor calculation methods

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