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Equation determination

In the MPPT/MBPT method, once the reference CSF is chosen and the SCF orbitals belonging to this CSF are detennined, the wavefiinction T and energy E are detennined in an order-by-order maimer. The perturbation equations determine what CSFs to include and their particular order. This is one of the primary strengdis of this technique it does not require one to make fiirtlier choices, in contrast to the MCSCF and Cl treatments where one needs to choose which CSFs to include. [Pg.2177]

When the Sehrodinger equation ean be separated to generate a time-independent equation deseribing the spatial eoordinate dependenee of the wavefunetion, the eigenvalue E must be returned to the equation determining F(t) to find the time dependent part of the wavefunetion. By solving... [Pg.13]

The boundary conditions, not the Sehrodinger equation, determine whether the eigenvalues will be discrete or continuous... [Pg.15]

The additivity of E and the separability of the equations determining the Cj eoeffieients make the MPPT/MBPT energy size-extensive. This property ean also be demonstrated for the Coupled-Cluster energy (see the referenees given above in Chapter 19.1.4). However, size-extensive methods have at least one serious weakness their energies do not provide upper bounds to the true energies of the system (beeause their energy funetional is not of the expeetation-value form for whieh the upper bound property has been proven). [Pg.490]

Tor each of the following equations, determine the optimum response, using the one-factor-at-a-time searching algorithm. Begin the search at (0, 0) with factor A, and use a step size of 1 for both factors. The boundary conditions for each response surface are 0 < A < 10 and 0 < B < 10. Continue the search through as many cycles as necessary until the optimum response is found. Compare your optimum response for each equation with the true optimum. [Pg.700]

In postulating a statistieal model for a statie stress variable, it is important to distinguish between brittle and duetile materials (Bury, 1975). For simple stress systems, i.e. uniaxial or pure torsion, where only one type of stress aets on the eomponent, the following equations determine the failure eriterion for duetile and brittle types to prediet the reliability (Haugen, 1980) ... [Pg.192]

Previous equations determine the pressure drop across the tube bundle. For the additional drop for flow through the free area above, below, or around the segmental baffles use... [Pg.28]

For final calculation use from Figures 7-23 or 7-24 and substitute in the above equation. Determine the needed Reynolds number, Re, using the next size larger orifice. Area is determined from that made in the first trial calculation [33]. [Pg.441]

To select the proper sizing equation, determine whether the flowing conditions are sonic or subsonic from the equations. When the absolute pressure downstream or exit of the throat is less than or equal to the critical flow pressure, P., then the flow is critical and the designated equations apply [33a]. WTien the downstream pressure exceeds the critical flow pressure, P,., then sub-... [Pg.459]

To illustrate the use of the above equation, determine the catalyst circulation rate from the following information ... [Pg.223]

Complete the following equations. Determine the net potential of such a cell and decide whether reaction can occur. [Pg.222]

Substituting Vs and VL into the above equation determines the volumetric mass transfer coefficient. Volumetric mass transfer coefficient is calculated as ... [Pg.277]

These equations determine the conditions under which the correspondence between the generating solution (6-64) and the original nonlinear differential equation (6-63) is assured. [Pg.355]

The rate equations determine the rate of change of the probability of a particular configuration, a, within an ensemble of growing crystals. They must include the rate constants for adding or subtracting units, which are assumed to obey microscopic reversibility. The net flux between configurations a and a which occur with probability P(a) and P(a ) respectively, and differ by one unit is ... [Pg.298]

Derivation of the isotropic Q-branch spectra for the case of linear molecules is analogous to the case for spherical molecules. The integral part of the kinetic equation determines the set of eigenfunctions of the collisional operator... [Pg.264]

In order to close the system of Eqs. (8.1-8.3) it is necessary to supplement the gas equation of state and the equation determining the dependence of liquid density on temperature... [Pg.353]

Having calculated the force for a particular event the slip is calculated using the bush model and hence the energy dissipation is obtained. Using the factors of the abrasion equation, determined with the LAT 100 on an alumina surface the abrasion loss for each event is calculated. The forces are different for a driven and a nondriven axle and accordingly different abrasion rates will result. [Pg.750]

It can be shown that Equation 34 Is the YBG equation determining the density distribution n(x) of the fluid. With the Flscher-Methfessel closure, the density distribution Is all that Is needed to calculate the coefladents M (x) and M2(x). Integrating Equation 35, we And... [Pg.265]

This equation determines a rank-1 matrix, and the eigenvector of its only one nonzero eigenvalue gives the direction dictated by the nonadiabatic couphng vector. In the general case, the Hamiltonian differs from Eq.(l), and the Hessian matrix has the form... [Pg.102]

The equation determining the optimum orbitals of polyelectronic systems in the case of the SCF and MCSCF theories can be written in the form ... [Pg.22]

These simultaneous linear homogeneous equations determine c and C2 and have a non-trivial solution if the determinant of the coefficients of c, C2 vanishes... [Pg.78]

The dynamical elastic and inelastic scattering ofhigh-energy electrons by solids may be described by three fundamental equations [5]. The first equation determines the wave amplitude G ( r, r, E), or the Green function, at point r due to a point source of electrons at r in the averaged potential (V (r)) ... [Pg.160]

Example 11.2 Using the Underwood Equations, determine the best distillation sequence, in terms of overall vapor load, to separate the mixture of alkanes in Table 11.2 into relatively pure products. The recoveries are to be assumed to be 100%. Assume the ratio of actual to minimum reflux ratio to be 1.1 and all columns are fed with a saturated liquid. Neglect pressure drop across each column. Relative volatilities can be calculated from the Peng-Robinson Equation of State with interaction parameters assumed to be zero (see Chapter 4). Determine the rank order of the distillation sequences on the basis of total vapor load for ... [Pg.214]

A critical comparison between experiment and theory is hindered by the range of experimental values reported in the literature for each molecule. This reflects the difficulty in the measurement of absolute ionization cross sections and justifies attempts to develop reliable semiempirical methods, such as the polarizability equation, for estimating the molecular ionization cross sections which have not been measured or for which only single values have been reported. The polarizability model predicts a linear relationship between the ionization cross section and the square root of the ratio of the volume polarizability to the ionization potential. Plots of this function against experimental values for ionization cross sections for atoms are shown in Figure 7 and for molecules in Figure 8. The equations determined... [Pg.346]

Assuming that the concentration of the gas molecules CB is little affected by clustering, the following two equations determine the equilibrium concentrations of clusters of various sizes C, n = 0, 1, 2,. .. ... [Pg.139]

Suppose that the particle at the site n = 0 has the mass mc = m - Am different from the mass m of the other particles. The equation determining GF for... [Pg.142]

Alternatively, the conservation of atomic species is commonly expressed in the form of chemical equations, corresponding to chemical reactions. We refer to the stoichiometric constraints expressed this way as chemical reaction stoichiometry. A simple system is represented by one chemical equation, and a complex system by a set of chemical equations. Determining the number and a proper set of chemical equations for a specified list of species (reactants and products) is the role of chemical reaction stoichiometry. [Pg.7]

It is sometimes stated as a rule of thumb that the rate of a chemical reaction doubles for a 10 K increase in T. Is this in accordance with the Arrhenius equation Determine the... [Pg.44]

Ethyl formate is to be produced from ethanol and formic acid in a continuous flow tubular reactor operated at a constant temperature of 303 K (30°C). The reactants will be fed to the reactor in the proportions 1 mole HCOOH 5 moles C2H5OH at a combined flowrate of 0.0002 m3/s (0.72 m3/h). The reaction will be catalysed by a small amount of sulphuric acid. At the temperature, mole ratio, and catalyst concentration to be used, the rate equation determined from small-scale batch experiments has been found to be ... [Pg.262]

Given the following reversible equation, determine which species is or are Brpnsted acids. [Pg.178]

Detailed modeling study of practical sprays has a fairly short history due to the complexity of the physical processes involved. As reviewed by O Rourke and Amsden, 3l() two primary approaches have been developed and applied to modeling of physical phenomena in sprays (a) spray equation approach and (b) stochastic particle approach. The first step toward modeling sprays was taken when a statistical formulation was proposed for spray analysis. 541 Even with this simplification, however, the mathematical problem was formidable and could be analyzed only when very restrictive assumptions were made. This is because the statistical formulation required the solution of the spray equation determining the evolution of the probability distribution function of droplet locations, sizes, velocities, and temperatures. The spray equation resembles the Boltzmann equation of gas dynamics[542] but has more independent variables and more complex terms on its right-hand side representing the effects of nucleations, collisions, and breakups of droplets. [Pg.325]

Kelvin s equation determines the equilibrium vapor pressure over a curved meniscus of liquid ... [Pg.265]

By using Clarke s Equation determine the dose of Tegretol for a child weighing 62 lb. The usual adult dose of Tegretol is 100 mg bid. [Pg.279]

Let s learn to apply the preceding equation. Determine the freezing point of an aqueous solution containing 10.50 g of magnesium bromide in 200.0 g of water. [Pg.185]


See other pages where Equation determination is mentioned: [Pg.457]    [Pg.338]    [Pg.275]    [Pg.861]    [Pg.232]    [Pg.564]    [Pg.253]    [Pg.415]    [Pg.31]    [Pg.251]    [Pg.12]    [Pg.284]   


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Determinant equation

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