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Calculations, field

Some people use calculators or computers. I have my K E slide rule. I used to be a computer guy in the days of punch cards and Fortran. But I always take an electrochemical computer with me on all field troubleshooting assignments. It fits compactly beneath my hard hat. [Pg.538]

The ability to manipulate field data as it is obtained is the best way to speed success in field troubleshooting. For example, how much air is leaking into the incinerator duct at the sulfur plant in Aruba What size hole in the duct is needed to allow this much air leakage I can calculate the air flow based on the observed temperature rise in the duct due to afterburning of hydrogen sulfide in the incinerator effluent. Now I know that I need to find, and did find just yesterday, a 4-in by 4-in hole in the duct. [Pg.538]

Most of the equations you will need for common process equipment have been presented in the proceeding chapters. One of the purposes that we had in writing this book was to make such information available for field troubleshooting. [Pg.539]


For the field calculation it more convenient to use a tx(B) curve than the normal ix(H) curve because the calculated vector potential A is derived from the flux density B. This ii(B) curve however can be calculated easily from the measured values. [Pg.314]

This Blume-Eiiiery-GrifSths (BEG) model [74] has been studied both by mean field calculations as well as by simulations. There is no pronounced difference between the amphiphile molecules S= 0, the oil or the water. Indeed, the model was first suggested in a quite different context. An extension of the model by Schick and Shih [75] includes an additional interaction of tlie fomi... [Pg.2379]

The program system COBRA [118, 119] can be regarded as a rule- and data-based approach, but also applies the principles of fragment-based (or template-based) methods extensively (for a detailed description sec Chapter 11, Sections 7.1 and 7.2 in the Handbook). COBRA uses a library of predefined, optimized 3D molecular fragments which have been derived from crystal structures and foi ce-field calculations. Each fi agment contains some additional information on... [Pg.98]

D information is available, e.g., in databases without experimental data, the different types of surfaces (sec below) can be calculated only after a 3D structure has been determined by a 3D structure generator, which might be followed by computational refinement, e.g., with a force-field calculation. [Pg.125]

In order to represent 3D molecular models it is necessary to supply structure files with 3D information (e.g., pdb, xyz, df, mol, etc.. If structures from a structure editor are used directly, the files do not normally include 3D data. Indusion of such data can be achieved only via 3D structure generators, force-field calculations, etc. 3D structures can then be represented in various display modes, e.g., wire frame, balls and sticks, space-filling (see Section 2.11). Proteins are visualized by various representations of helices, / -strains, or tertiary structures. An additional feature is the ability to color the atoms according to subunits, temperature, or chain types. During all such operations the molecule can be interactively moved, rotated, or zoomed by the user. [Pg.146]

Some of the stand-alone programs mentioned above have an integrated modular 3D visualization application (e.g., ChemWindow —> SymApps, ChemSketch —> ACD/3D Viewer, ChemDraw —> Chem3D). These relatively simple viewers mostly generate the 3D geometries by force-field calculations. The basic visualization and manipulation features are also provided. Therefore, the molecular models can be visualized in various display styles, colors, shades, etc. and are scalable, movable and rotatable on the screen. [Pg.146]

To understand the basic concepts of force field calculations... [Pg.319]

No Force Field Calculation Without Atom Types... [Pg.339]

This section descrihes IlyperChem s four force fields, MM-h AMBER, OPES, and BlO-h providing auxiliary information for all force field calculations. [Pg.173]

In general, we know bond lengths to within an uncertainty of 0.00.5 A — 0.5 pm. Bond angles are reliably known only to one or twx) degrees, and there arc many instances of more serious angle enxirs. Tn addition to experimental uncertainties and inaccuracies due to the model (lack of coincidence between model and molecule), some models present special problems unique to their geometry. For example, some force fields calculate the ammonia molecule. Nlln to be planar when there is abundant ex p er i m en ta I evidence th at N H is a 11 i g o n a I pyramid. [Pg.113]

The Poisson equation has been used for both molecular mechanics and quantum mechanical descriptions of solvation. It can be solved directly using numerical differential equation methods, such as the finite element or finite difference methods, but these calculations can be CPU-intensive. A more efficient quantum mechanical formulation is referred to as a self-consistent reaction field calculation (SCRF) as described below. [Pg.209]

The observation of the variation of the SCH bands of thiazole with the nature and the position of the substituent has been interpreted as a proof of a fairly strong coupling between the various CH vibrators (203). The couplings are confirmed by the force-field calculation for thiazole that shows that the nature of the 1300-1000 band is rather complex. [Pg.58]

Focuses on force field calculations for understanding the dynamic properties of proteins and nucleic acids. Provides a useful introduction to several computational techniques, including molecular mechanics minimization and molecular dynamics. Includes discussions of research involving structural changes and short time scale dynamics of these biomolecules, and the influence of solvent in these processes. [Pg.4]

Force field calculations often truncate the non bonded potential energy of a molecular system at some finite distance. Truncation (nonbonded cutoff) saves computing resources. Also, periodic boxes and boundary conditions require it. However, this approximation is too crude for some calculations. For example, a molecular dynamic simulation with an abruptly truncated potential produces anomalous and nonphysical behavior. One symptom is that the solute (for example, a protein) cools and the solvent (water) heats rapidly. The temperatures of system components then slowly converge until the system appears to be in equilibrium, but it is not. [Pg.29]

Restraints add potential terms to a force field calculation, favoring the value that you specify in a restraint. The larger the value of the h arm on ic force con stan t, th e m ore tigh tly th e calculation restrain s the value. [Pg.81]

Raffenetti, R.C. Pre-processing two-electron integrals for efficient utilization in many-electron self-consistent field calculations. Chem. Phys. LeUera 20 335-338, 1973. [Pg.114]


See other pages where Calculations, field is mentioned: [Pg.313]    [Pg.2332]    [Pg.2377]    [Pg.2378]    [Pg.100]    [Pg.147]    [Pg.349]    [Pg.353]    [Pg.4]    [Pg.29]    [Pg.107]    [Pg.235]    [Pg.138]    [Pg.228]    [Pg.252]    [Pg.252]    [Pg.156]    [Pg.223]    [Pg.232]    [Pg.248]    [Pg.361]    [Pg.107]    [Pg.235]    [Pg.164]    [Pg.164]    [Pg.128]    [Pg.62]    [Pg.327]    [Pg.631]    [Pg.633]    [Pg.634]   
See also in sourсe #XX -- [ Pg.700 ]

See also in sourсe #XX -- [ Pg.538 ]




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A Self-Consistent Field Variational Calculation of IP for the Helium Atom

Ad hoc or transferable Force field fitting from ab initio calculations

And force-field calculations

Approximate methods of field calculation in induction logging

Atomic self-consistent field calculations

Calculating Thermodynamic Properties Using a Force Field

Calculation and Application of Molecular Interaction Fields

Calculation nonstationary fields

Calculation of Crystal Field Parameters

Calculation of fields

Calculation of the Molecular Interaction Field

Calculations, field gradient

Cavity fields total energy calculations

Closed-shell molecule, self-consistent field configuration, calculation

Comparative molecular field analysis property calculations

Complete active self-consistent field calculation

Complete active space self-consistent field CASSCF) calculations

Complete active space self-consistent field CASSCF/CASPT2 calculations

Complete active space self-consistent field calculations, with

Complex self-consistent field calculations

Computational force field calculations

Computer codes field calculations

Copper complexes crystal-field calculations

Coupled self-consistent field calculations

Crystal field theory calculations

Crystal-field calculations

Cyclohexane force field calculation

Diffusion theory self-consistent field calculations

Electric field gradient calculation

Electric field, calculation

Electric field, calculation effect

Electric fields, static finite-difference calculations

Electronic states Self-consistent field calculations, electron

Empirical force field calculations, hydrogen

Empirical force field calculations, hydrogen bonding

Empirical force-field calculations

Empirical force-field calculations limitations

Field flow fractionation calculations

Field-Theoretic Calculation

Fields free energy calculations

Finite Field Calculations of Raman Intensities

Finite Volume Method for Calculation of Flow Field

Finite-field calculations

Finite-field method polarizability calculations

Fixed-charges, polarizable force field calculations

Force Field Calculations Structural Organic Chemistry

Force Field, Virial Calculation of Stress

Force Fields and Molecular Mechanics Calculations

Force field calculations, vibrational

Force field calculations, vibrational spectroscopy

Force field for molecular mechanic calculations

Force fields from ab initio calculations

Force-field calculations

Force-field calculations. See

Force-field energies, calculated

Force-field methods, calculation

Force-field methods, calculation of molecular structure and energy

Halides, force field calculations with

Hartree, self consistent field calculations

Hartree-Fock and Self-Consistent-Field Calculations

Hartree-Fock calculations space self-consistent field

Hartree-Fock self-consistent field energy calculations

Hartree-Fock self-consistent-field calculations

Ligand field calculations

Ligand field calculations plastocyanin

Ligand field stabilization energy calculation

Ligand field theory calculations

MMX force field calculations

Magnetic field effects calculation

Mass calculated dispersion field

Mean-field calculation

Mean-velocity field calculations

Molecular structure and energy calculation of, by force-field

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

Monte Carlo-self-consistent field calculations

Multiconfiguration self-consistent field calculations

Multiconfigurational self-consistent field calculations

Multireference self-consistent-field calculation

Near-field integral calculation

Near-fields calculation scoping

Polymer adsorption models in field calculations

Post Self-Consistent Field Calculations

Protein Data Bank force field calculations

Quantum chemical calculations self-consistent field theory

Resonant field positions, calculation

Resonant field positions, calculation Resonator

Self-consistent field Xa scattered wave calculations

Self-consistent field calculation definition

Self-consistent field calculation with potential well

Self-consistent field calculations

Self-consistent field calculations models

Self-consistent field calculations molecules

Self-consistent field calculations principles

Self-consistent field calculations, computer codes

Self-consistent field calculations, role

Self-consistent field calculations, solute-solvent interaction

Self-consistent field methods, effective nuclear charge calculated using

Self-consistent field relativistic calculations

Self-consistent field shielding calculations

Self-consistent field theory Hartree-Fock electronic structure calculations

Self-consistent reaction field calculation

Self-consistent-field calculations theory

Selfconsistent field calculations

Sensitivity of Calculated Free Energies to Force Field Parameters

Theoretical calculations self-consistent field

Westheimer empirical force field calculations

Westheimer force field calculations

Zeolite force field calculations

Zero-field splitting parameters, calculations

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