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Effective Quantities

The effective mass rrih of a moving molecule consists of the mass mi of the dry macromolecule of molecular weight Mi and the mass m of the solvent carried along with the macromolecule. If the mass of the solvent carried is expressed as a multiple Th = m j mi of the polymer mass, the following is then obtained for the effective mass of the molecule  [Pg.251]

The effective volume Vh is composed, analogously, of the volume of the dry macromolecule and that of the solvent moving with the macromolecule, where the volumes are replaceable by the specific volumes V2 and vi  [Pg.252]

The specific volume vi of the solvent in the macromolecule is different from the specific volume vi of the pure solvent, since part of the solvent which is in the macromolecule will undergo a specific interaction (solvation) with the macromolecule. The other part will be dragged along purely mechanically. The total volume V of the solution of a total mass m of solvent and mass m2 of dry macromolecule is thus given as [Pg.252]


By virtue of their simple stnicture, some properties of continuum models can be solved analytically in a mean field approxunation. The phase behaviour interfacial properties and the wetting properties have been explored. The effect of fluctuations is hrvestigated in Monte Carlo simulations as well as non-equilibrium phenomena (e.g., phase separation kinetics). Extensions of this one-order-parameter model are described in the review by Gompper and Schick [76]. A very interesting feature of tiiese models is that effective quantities of the interface—like the interfacial tension and the bending moduli—can be expressed as a fiinctional of the order parameter profiles across an interface [78]. These quantities can then be used as input for an even more coarse-grained description. [Pg.2381]

An isobole is a contour line representing equi-effective quantities of two agents or their mixtures (Loewe and Muischnek 1926). [Pg.377]

It is important to note that the effective density (r) must be everywhere semipositive definite so that all effective quantities are then properly defined. Within the WDA, the explicit enforcement of the sum rule [see Eq. (127)]... [Pg.148]

Let us introduce the effective quantities—the zone width aq, the temperature in the reaction zone T), and the concentrations oq and bv The total amount of matter reacting throughout the zone is expressed in terms of these effective quantities... [Pg.314]

From the work of O Brien [7] we infer that it should be possible to simulate the EPR spectra of CaO Cu2+ using a single-mode vibronic model, but in doing so the values for the parameters should be regarded as effective quantities. [Pg.473]

Notation. relative permittivity, K -imaginary relative permittivity, A-surface conduction, subscript "elT" denotes an effective quantity, f frequency, vv vvater content... [Pg.247]

In Equations (2.178) the effective quantities indicated with a tilde have the same meaning described above. [Pg.242]

Although this is phrased in the language of a single oscillating particle, it is equivalent to the equation for normal modes, where kh, bd, me, and e are effective quantities describing entire collective oscillations. There are several special cases of e2/(/ch - i(obi — co2me) for certain further idealized forms of response. [Pg.253]

However, in many practical situations the problem exists that effective rate constants and activation energies have been derived on the basis of laboratory experiments. The question arises then as to whether or not these parameters arc influenced by transport effects. With the relations given so far, this question cannot be answered yet, since according to its definition by cq 27 the Thiele modulus is based on the intrinsic rate constant k. This problem can be solved by introducing a new modulus, which in contrast to only contains observable (effective) quantities, and thus can... [Pg.334]

Some applications of the method will be shown for the ternary salt trimethylammonium (TMA)-TCNQ-I. Tanner et al. [43] have obtained a best fit with a Drude-Lorentz dielectric function with a>p = 5290 cm-1, -y = 2560 cm"1, ec = 2.65, , is the frequency and T is the relaxation rate of the second oscillator. The average value of the frequency-dependent conductivity below 200 cm"1 should be 19 IS- cm"1. The energy gap of 0.10 to 0.14 eV, the effective quantity of electrons participating in the electric transport Ncfi = 0.67 per molecule, and the effective mass of the carriers m = 5.2 m were found from the plasma frequency. [Pg.244]

However, molecular parameters obtained in this way are often only effective quantities without physical significance. Furthermore, if the molecule executes large-amplitude vibrations, the number of these parameters becomes unmanageably large. [Pg.100]

With his article, Guyton characterized chemical affinity as a broad frontier of theoretical inquiry that would ultimately absorb pneumatic studies. His discussion identified three important problems in the current investigations of affinity the determination of saturation capacities, the effect of contingent factors on chemical reactions, and reciprocal affinity. These problems took on urgency in the efforts to classify and control the operations of salts. Guyton s systematic reflection on affinity, particularly his efforts to discern disturbing physical forces and his notion of effective quantities, provided a starting point for Berthollet s chemical statics. [Pg.370]

If saturation capacities seemed to promise an easy way of measuring relative affinities, Berthollet tagged on other considerations to complicate the scheme further. He considered liquid as the ideal medium for chemical action, since it allowed the substances to exercise their full power. The quantity of the substances that constituted chemical mass did not necessarily coincide with the amount that was put into the solution, but referred to the effective quantity, or the quantity within the sphere of action. Technically, concentration was more likely to fit... [Pg.424]

Effective quantities of ozone dissolved in water during disinfection, injecting 0.25 and 0.50 gram of O3 respectively, per cubic meter of water Di—Di. Limit at which end of destruction of 6. coli has been verified in strongly infected water (7,000,000 6. coli per 100 ml. of water) Welsbach (W) and Torricelli (T) processes with Welsbach ozonator... [Pg.458]

It is usually difficult to observe visually a change in floe structure in a concentrated slurry. The two best indications that an effective quantity of chemical has been added is a sudden thickening or increase in viscosity of the slurry and the formation of riveriets on the surface of a spatula when treated slurry is shaken from it. It is generally necessary to exceed a threshold quantity of chemical before there is a measurable improvement. The proper dosage becomes an economic balance between the cost of additional chemicals and the savings resulting from a reduction in filter area. [Pg.2019]

Another possible approach to the evaluation of the required effective quantities is to start with the effective entropy change. Hill [98,99] considered the statistical mechanics of the localized unimolecular adsorption on heterogeneous surfaces to propose formulae for the configurational entropy. [Pg.169]

Eq. (8) is similar to Eq. (7) however, the effective quantities and in Eq. (8) are defined differently. In fact, they can be transformed into each other by interchanging the subscripts <->--L and the material parameters K K, rji <-> r]2 and 0 2 -0 3. These transformations are natural consequences of switching the boundary conditions between planar and homeotropic cases. [Pg.67]

The enterprise analyzes alternatives of 6.5.2 to determine availability of an off-the-shelf item (nondevelop-mental hardware or software). Each identified off-the-shelf item must be assessed to determine cost effectiveness, quantity, availability, supportability, and viability of the supplier and/or their product. [Pg.49]


See other pages where Effective Quantities is mentioned: [Pg.1694]    [Pg.132]    [Pg.27]    [Pg.280]    [Pg.409]    [Pg.69]    [Pg.231]    [Pg.107]    [Pg.109]    [Pg.96]    [Pg.84]    [Pg.231]    [Pg.233]    [Pg.115]    [Pg.259]    [Pg.107]    [Pg.425]    [Pg.660]    [Pg.103]    [Pg.907]    [Pg.58]    [Pg.94]    [Pg.302]    [Pg.29]    [Pg.251]    [Pg.365]   


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