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Point function

Equation (22-106) gives a permeate concentration as a function of the feed concentration at a stage cut, 0 = 0, To calculate permeate composition as a function of 0, the equation may be used iteratively if the permeate is unmixed, such as would apply in a test cell. The calculation for real devices must take into account the fact that the driving force is variable due to changes on both sides of the membrane, as partial pressure is a point function, nowhere constant. Using the same caveat, permeation rates may be calciilated component by component using Eq. (22-98) and permeance values. For any real device, both concentration and permeation require iterative calculations dependent on module geometiy. [Pg.2048]

Static pre.s.sure is the pressure of the moving fluid. The static pressure of a gas is the same in all directions and is a scalar point function. It can be measured by drilling a hole in the pipe and keeping a probe flush with the pipe wall. [Pg.113]

The above results show that the structure of the system with the molecules self-assembled into the internal films is determined by their correlation functions. In contrast to simple fluids, the four-point correlation functions are as important as the two-point correlation functions for the description of the structure in this case. The oil or water domain size is related to the period of oscillations A of the two-point functions. The connectivity of the oil and water domains, related to the sign of K, is determined by the way four moleeules at distanees eomparable to their sizes are eorrelated. For > 0 surfactant molecules are correlated in such a way that preferred orientations... [Pg.736]

Let s discuss the reaction rate computations based on the kinetic model with those derived from the experiments. At a given instant, these calculations are essentially "point" functions since they are independent of the path the reaction system has taken up to that given instant. [Pg.353]

Suppose that 4> x,y,z) is a scalar point function, that is, a scalar function that is uniquely defined in a given region. Under a change of coordinate system to, say, x y z, it will take on another form, although its value at any point remains the same. Applying the chain rule (Section 2.12),... [Pg.252]

In order to probe the effect of junction point functionality on chain conformation and morphology of miktoarm star block copolymer architectures, a series of PI PS (n = 2, 4, 16) was synthesized [166]. A single batch of both living PS and PI arms have been used, in order to ensure that all chemically identical arms (either A or B) have the same molecular weights. The living A and B chains were reacted with the appropriate chlorosilane, under appropriate experimental conditions, to produce the corresponding //-stars, as shown in Scheme 88. [Pg.101]

Then the Li-dependent four-point function at leading order in 1/N, at zero external momenta, has the formal expression... [Pg.211]

Notice that, taking = +1, we obtain the auxiliary doubled two-point function which must be used for calculating the fermionic propagator. [Pg.220]

HTL quasiparticle model. In QCD, the truncation of a resummation scheme based on 2-point functions is delicate because of gauge invariance. [Pg.138]

The validity of the t Hooft anomaly conditions at high matter density have been investigated in [32, 33], A delicate part of the proof presented in [33] is linked necessarily to the infrared behavior of the anomalous three point function. In particular one has to show the emergence of a singularity (i.e. a pole structure). This pole is then interpreted as due to a Goldstone boson when chiral symmetry is spontaneously broken. [Pg.161]

Equation 9-4 and related heats of reaction can be manipulated to show that the maximum efficiency is a state point function, regardless of path (steam reforming, partial oxidation, or autothermal reforming), and is achieved at the thermoneutral point. In practice, x is set slightly higher than the thermoneutral point so that additional heat is generated to offset heat losses from the reformer. Table 9-1 presents efficiencies at the thermoneutral point for various hydrocarbon fuels. [Pg.212]

The dendrimer framework also plays an important role. The catalytic performance measured by activity, selectivity, stability, and recyclability depends on the dendritic architecture, and it is important to distinguish periphery-functionalized, core-functionalized, and focal point-functionalized dendrimers (Fig. 1). Periphery-functionalized dendrimers have catalytic groups located at the surface where they are directly available to the substrate. In contrast, when a dendrimer is functionalized at its core, the substrate has to penetrate the dendrimer support before it reaches the active center, and this transport process can limit the rate of a catalytic reaction if large and congested dendrimers are involved. [Pg.72]

In core- (and focal point-) functionalized dendrimers, the catalyst may benefit from the site isolation created by the environment of the dendritic structure. Site-isolation effects in dendrimers can also be beneficial for other functionalities (a review of this topic has appeared in Reference (10)). When reactions are deactivated by excess ligand and when a bimetallic deactivation mechanism is operative, core-functionalized dendrimers can minimize the deactivation. [Pg.73]

Btiilding on atomic studies using even-tempered basis sets, universal basis sets and systematic sequences of even-tempered basis sets, recent work has shown that molecular basis sets can be systematically developed until the error associated with basis set truncation is less that some required tolerance. The approach has been applied first to diatomic molecules within the Hartree-Fock formalism[12] [13] [14] [15] [16] [17] where finite difference[18] [19] [20] [21] and finite element[22] [23] [24] [25] calculations provide benchmarks against which the results of finite basis set studies can be measured and then to polyatomic molecules and in calculations which take account of electron correlation effects by means of second order perturbation theory. The basis sets employed in these calculations are even-tempered and distributed, that is they contain functions centred not only on the atomic nuclei but also on the midpoints of the line segments between these nuclei and at other points. Functions centred on the bond centres were found to be very effective in approaching the Hartree-Fock limit but somewhat less effective in recovering correlation effects. [Pg.159]

The RNA product may encode transfer RNAs (tRNAs), ribosomal RNAs (rRNAs), or small nuclear RNAs (snRNAs) that have end point functions in the cell. [Pg.185]

The static pressure in a flnid has the same vmue in all directions and can be considered as a scalar point function. It is the pressure of a flowing fluid. It is normal to the surface on which it acts and at any given point has the same magnitude irrespective of the orientation of the surface. The static pressure arises because of the random motion in the fluid of the molecules that make up the fluid. In a diffuser or nozzle, there is an increase or decrease in the static pressure due to the change in velocity of the moving fluid. [Pg.6]

THRESHOLD NOT ATTAINED ESTINATE OF THE MINIMUM POINT FUNCTION VALUE AT THE FINAL ESTINATE GRADIENT VECTOR AT THE FINAL ESTINATE ESTINATE OF THE INVERSE HESSIAN NATRIX... [Pg.120]

NUMBER OF 6RID POINTS FUNCTION VALUES AT GRID POINTS... [Pg.232]

Branch-point functionalities 3 and 4 correspond respectively to a normal branching reaction and to cross-linking without cyclizatioa Some of the papers referred to above contain results for other types of structure. ... [Pg.11]

Expansion is considered for finite, regular polyethylene stars perturbed by the excluded volume effect. An RIS model is used for the chain statistics. The number of bonds in each branch ranges up to 10 240, and the functionality of the branch point ranges up to 20. The form of the calculation employed here provides a lower bound for the expansion. If the number, n, of bonds in the polymers is heid constant, expansion is found to decrease with increasing branch point functionality. Two factors dictate the manner in which finite stars approach the limiting behavior expected for very large stars, These two factors are the chain length dependence at small n of the characteristic ratio and of fa -a3) / n1/2. [Pg.409]

Actually, this I(S) can be expressed explicitly in terms of an informationminimizing 3F which, as will be shown in Section VII, can be found as a locally canonical distribution (cf. the zero th approximation in the Chapman-Enscog process). We will denote it by E it is a functional of p, m , E and a point function of (x) on... [Pg.46]

Banks, W.H. 1939. Considerations of a vapor pressure-temperature equation, and their relationship to Burnop s boiling point function. ]. Chem. Soc. 1939 292ff. [Pg.69]


See other pages where Point function is mentioned: [Pg.2048]    [Pg.122]    [Pg.1301]    [Pg.58]    [Pg.36]    [Pg.46]    [Pg.46]    [Pg.115]    [Pg.200]    [Pg.161]    [Pg.100]    [Pg.102]    [Pg.198]    [Pg.535]    [Pg.136]    [Pg.38]    [Pg.98]    [Pg.128]    [Pg.527]    [Pg.180]    [Pg.16]    [Pg.231]    [Pg.91]    [Pg.91]   
See also in sourсe #XX -- [ Pg.493 ]




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Boiling point as a function

Complex function saddle point

Critical points model dielectric function

Diblock copolymers junction-point-functionalized

Disconnection at a Functional Group or Branch Point

Focal point-functionalized dendrimers

Four-point correlation function

Function point analysis

Functionality of a branch point

Functions having degenerate critical points

General functions saddle points

Melting Point of Ice as a Function

Melting Point of Ice as a Function Pressure

Melting point ice, as function of pressure

Melting point mercury, as function of pressure

Methods, Pulse Sequences, and the Point Spread Function

One-Point Non-Equilibrium Correlation Functions

One-point probability density function

Operational functions function-point analysis

Physiological Functions and Attack Points of NO

Point group symmetry electronic wave function

Point spread function deconvolution

Point-spread function

Point-spread-function PSF

Regular points of potential functions

Scalar point function

Swelling and partition function of an isolated chain at the tricritical point

Two-Point Approximate Orbital-Free Kinetic Energy Functionals

Two-Point Non-Equilibrium Correlation Functions

Wave function analysis critical points

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