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Functional dependency

These happen to be already minimal. The corresponding structure function is [Pg.383]

By introducing pseudo-events the fault tree becomes more complex. This may lead to a more laborious evaluation. [Pg.383]

In such a case the probability is assigned to the primary events on the basis of the corresponding failure rates for independent failures. The fault tree of Fig. 9.35 has the following cut sets  [Pg.383]

After eliminating the non-minimal cut sets the following minimal cut sets remain  [Pg.383]

It is obvious that the failure of instrument air alone is sufficient to cause the undesired event. The structure function representing the fault tree is [Pg.383]


The electronic energy W in the Bom-Oppenlieimer approxunation can be written as W= fV(q, p), where q is the vector of nuclear coordinates and the vector p contains the parameters of the electronic wavefimction. The latter are usually orbital coefficients, configuration amplitudes and occasionally nonlinear basis fiinction parameters, e.g., atomic orbital positions and exponents. The electronic coordinates have been integrated out and do not appear in W. Optimizing the electronic parameters leaves a function depending on the nuclear coordinates only, E = (q). We will assume that both W q, p) and (q) and their first derivatives are continuous fimctions of the variables q- and py... [Pg.2332]

The gradient of the PES (force) can in principle be calculated by finite difference methods. This is, however, extremely inefficient, requiring many evaluations of the wave function. Gradient methods in quantum chemistiy are fortunately now very advanced, and analytic gradients are available for a wide variety of ab initio methods [123-127]. Note that if the wave function depends on a set of parameters X], for example, the expansion coefficients of the basis functions used to build the orbitals in molecular orbital (MO) theory. [Pg.267]

Since the form of the electronic wave functions depends also on the coordinate p (in the usual, parametric way), the matrix elements (21) are functions of it too. Thus it looks at first sight as if a lot of cumbersome computations of derivatives of the electronic wave functions have to be carried out. In this case, however, nature was merciful the matrix elements in (21) enter the Hamiltonian matrix weighted with the rotational constant A, which tends to infinity when the molecule reaches linear geometry. This means that only the form of the wave functions, that is, of the matrix elements in (21), in the p 0 limit are really needed. In the above mentioned one-elecbon approximation... [Pg.486]

I he function/(r) is usually dependent upon other well-defined functions. A simple example 1)1 j functional would be the area under a curve, which takes a function/(r) defining the curve between two points and returns a number (the area, in this case). In the case of ni l the function depends upon the electron density, which would make Q a functional of p(r) in the simplest case/(r) would be equivalent to the density (i.e./(r) = p(r)). If the function /(r) were to depend in some way upon the gradients (or higher derivatives) of p(r) then the functional is referred to as being non-local, or gradient-corrected. By lonlrast, a local functional would only have a simple dependence upon p(r). In DFT the eiK igy functional is written as a sum of two terms ... [Pg.147]

Spherically symmetric (radial) wave functions depend only on the radial distance r between the nucleus and the election. They are the Is, 2s, 3s. .. orbitals... [Pg.22]

It is hardest to obtain precise values for the enthalpic values A, S, and G because they depend more heavily on high-energy states, which the system achieves infrequently. These functions depend on the actual value of Q, not just its derivatives. [Pg.15]

Other Interaction Processes. The selectivity of flotation reagents in a pulp and their functions depend on their interactions with the mineral phases to be separated, but other physicochemical and hydrodynamic processes also play roles. AH adsorption—desorption phenomena occur at the sohd—hquid interfacial region. Surface processes that influence such adsorptions include activation and depression. Activators and depressants are auxiUary reagents. [Pg.49]

Comparison of equations 10 and 11 shows that the factors and are similar iu their functional dependencies on kiln fill fraction. The... [Pg.50]

Structure. The stmctures of hides and skins are dependent on the needs of the animal and its environment. The functions of an animal s skin include protection from predators and infection, and maintenance of body temperature. The relative importance of these functions depends on the animal. Methods by which the skin accomplishes these functions is the same for most mammals. [Pg.80]

State Functions State functions depend only on the state of the system, not on past history or how one got there. If r is a function of two variables, x and y, then z x,y) is a state function, since z is known once X and y are specified. The differential of z is... [Pg.444]

When the function involved in the equation depends upon only one variable, its derivatives are ordinary derivatives and the differential equation is called an ordinaiy differential equation. When the function depends upon several independent variables, then the equation is called a partial differential equation. The theories of ordinaiy and partial differential equations are quite different. In almost eveiy respect the latter is more difficult. [Pg.453]

Temperature, pressure, and composition are thermodynamic coordinates representing conditions imposed upon or exhibited by the system, andtne functional dependence of the thermodynamic properties on these conditions is determined by experiment. This is quite direct for molar or specific volume which can be measured, and leads immediately to the conclusion that there exists an equation of. state relating molar volume to temperature, pressure, and composition for any particular homogeneous PVT system. The equation of state is a primaiy tool in apphcations of thermodyuamics. [Pg.514]

Each mechanism of breakage implies a different functional dependence of breakage rate on material properties. For the case of abrasive wear of ceramics due to surface scratching by loaded indentors, Evans Wilshaw [Acta Metallurgica, 24, 939 (1976)] determined a volumetric wear rate V of... [Pg.1887]

Low-molecular-weight products, generally secondary metabolites such as alcohols, carboxyhc and an iino acids, antibiotics, and vitamins, can be recovered using many of the standard operations such as liquid-hquid extraction, adsorption and ion-exchange, described elsewhere in this handbook. Proteins require special attention, however, as they are sufficiently more complex, their function depending on the integrity of a delicate three-dimensional tertiaiy structure that can be disrupted if the protein is not handled correctly. For this reason, this section focuses primarily on protein separations. Cell separations, as a necessary part of the downstrean i processing sequence, are also covered. [Pg.2056]

A new type of functional dependence follows from the equation of the conceptual retention model ... [Pg.81]

Compai ison with literature experimental and calculation data showed that the model proposed ensures the accurate behavior of the functional dependence of x-ray fluorescence intensity on the particle size. Its main advantage is the possibility to estimate the effect of particle size for polydispersive multicomponent substances. [Pg.113]

The referential formulation is translated into an equivalent current spatial description in terms of the Cauchy stress tensor and Almansi strain tensor, which have components relative to the current spatial configuration. The spatial constitutive equations take a form similar to the referential equations, but the moduli and elastic limit functions depend on the deformation, showing effects that have misleadingly been called strain-induced hardening and anisotropy. Since the components of spatial tensors change with relative rigid rotation between the coordinate frame and the material, it is relatively difficult to construct specific constitutive functions to represent particular materials. [Pg.119]

The deformation may be viewed as composed of a pure stretch followed by a rigid rotation. Stress and strain tensors may be defined whose components are referred to an intermediate stretched but unrotated spatial configuration. The referential formulation may be translated into an unrotated spatial description by using the equations relating the unrotated stress and strain tensors to their referential counterparts. Again, the unrotated spatial constitutive equations take a form similar to their referential and current spatial counterparts. The unrotated moduli and elastic limit functions depend on the stretch and exhibit so-called strain-induced hardening and anisotropy, but without the effects of rotation. [Pg.119]

In the second step, the spatial restraints and the CHARMM22 force field tenns enforcing proper stereochemistry [80,81] are combined into an objective function. The general form of the objective function is similar to that in molecular dynamics programs such as CHARMM22 [80]. The objective function depends on the Cartesian coordinates of —10,000 atoms (3D points) that form a system (one or more molecules) ... [Pg.283]

What does the answer to question 2 indicate about the functional dependence of ozone concentrations on the absolute magnitude of [NOj] = [NO] + [NO2] ... [Pg.178]

The selectivity observed in most intramolecular functionalizations depends on the preference for a six-membered transition state in the hydrogen-atom abstraction step. Appropriate molecules can be constmcted in which steric or conformational effects dictate a preference for selective abstraction of a hydrogen that is more remote from the reactive radical. [Pg.719]

Article Exemptions. You do not have to factor into threshold or release determinations quantities of a listed toxic chemical contained In an article when that article is processed or used at your facility. An article is defined as a manufactured item that is formed to a specific shape or design during manufacture, that has end-use functions dependent in whole or in part upon its shape or design during end-use, and that does not release a toxic chemical under normal conditions of the processing or use of that item at the facility. [Pg.26]

Thisisquiteinteresting—allthedatafromthedifferentexperimentsnowfallononecurve We notice that the data have distinct functional dependence, which is neither linear nor... [Pg.120]


See other pages where Functional dependency is mentioned: [Pg.127]    [Pg.326]    [Pg.274]    [Pg.2473]    [Pg.486]    [Pg.514]    [Pg.577]    [Pg.152]    [Pg.153]    [Pg.423]    [Pg.271]    [Pg.1150]    [Pg.562]    [Pg.621]    [Pg.2]    [Pg.6]    [Pg.6]    [Pg.269]    [Pg.129]    [Pg.316]    [Pg.386]    [Pg.54]    [Pg.93]    [Pg.1504]    [Pg.2048]    [Pg.268]    [Pg.61]    [Pg.596]   
See also in sourсe #XX -- [ Pg.228 ]




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Dependence functional

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