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Saturated theory

Super saturation theory. According to model (1), the two reactants A and B diffuse from opposite direction and co-exist in the gel until the solubility product reaches a critical value above which the nucleation occurs according to the reaction... [Pg.177]

Two additional illustrations are given in Figures 6 and 7 which show fugacity coefficients for two binary systems along the vapor-liquid saturation curve at a total pressure of 1 atm. These results are based on the chemical theory of vapor-phase imperfection and on experimental vapor-liquid equilibrium data for the binary systems. In the system formic acid (1) - acetic acid (2), <() (for y = 1) is lower than formic acid at 100.5°C has a stronger tendency to dimerize than does acetic acid at 118.2°C. Since strong dimerization occurs between all three possible pairs, (fij and not... [Pg.35]

Freed J H 1969 Theory of saturation and double resonance effects in ESR spectra. IV. Electron-nuclear triple resonance J. Chem. Rhys. 50 2271-2... [Pg.1588]

Freed J 1979 Theory of multiple resonance and ESR saturation In liquids and related media Multiple Electron Resonance Spectroscopy ed M M Dorlo and J H Freed (New York Plenum) ch 3, pp 73-142... [Pg.1589]

Many simple systems that could be expected to form ideal Hquid mixtures are reasonably predicted by extending pure-species adsorption equiUbrium data to a multicomponent equation. The potential theory has been extended to binary mixtures of several hydrocarbons on activated carbon by assuming an ideal mixture (99) and to hydrocarbons on activated carbon and carbon molecular sieves, and to O2 and N2 on 5A and lOX zeoHtes (100). Mixture isotherms predicted by lAST agree with experimental data for methane + ethane and for ethylene + CO2 on activated carbon, and for CO + O2 and for propane + propylene on siUca gel (36). A statistical thermodynamic model has been successfully appHed to equiUbrium isotherms of several nonpolar species on 5A zeoHte, to predict multicomponent sorption equiUbria from the Henry constants for the pure components (26). A set of equations that incorporate surface heterogeneity into the lAST model provides a means for predicting multicomponent equiUbria, but the agreement is only good up to 50% surface saturation (9). [Pg.285]

Fig. 2. Schematic representation for the two-film theory of gas transfer = partial pressure of gas Pj = partial pressure of the gas at the interface Cj = concentration of gas at time t, Cj = initial concentration of gas at the interface Cg = initial concentration of gas at t = 0 and S = gas saturation. Fig. 2. Schematic representation for the two-film theory of gas transfer = partial pressure of gas Pj = partial pressure of the gas at the interface Cj = concentration of gas at time t, Cj = initial concentration of gas at the interface Cg = initial concentration of gas at t = 0 and S = gas saturation.
For the theory of neutralization of the magnetic effect on the conductor in a non-magnetic shielding, refer to the continuous enclosures for isolated phase bus systems discussed in Section 31.2.2. As a result of non-magnetic shielding there will be no saturation of the iron core and the V-I characteristic of the reactor will remain almost linear. [Pg.849]

The examples that have been presented in this section illustrate the approach that is used to describe structure and reactivity effects within the framework of MO description of structure. In the chapters that follow, both valence bond theory and MO theory will be used in the discussion of structure and reactivity. Qualitative valence bond terminology is normally most straightforward for saturated systems. MO theory provides useful insights into conjugated systems and into effects that depend upon the symmetry of the molecules under discussion. [Pg.57]

The condition defined by equation (8) is met by adjustment of (Qg(3)) nd (T(3)). The pressures at the second stripping flow inlet and that of the outlet for solute (C) must be made equal, or close to equal, to prevent cross-flow. Scott and Maggs [7] designed a three stage moving bed system, similar to that described above, to extract pure benzene from coal gas. Coal gas contains a range of saturated aliphatic hydrocarbons, alkenes, naphthenes and aromatics. In the above theory the saturated aliphatic hydrocarbons, alkenes and naphthenes are represented by solute (A). [Pg.437]

According to the field charging theory, the external electric field drives ions to the aerosol particle until the repelling electric field prevents ions from reaching the surface of the particle. This condition corresponds to the saturation i.e, the particle has reached a stable value which cannot be exceeded. The relationship between the net charge of the particle and charging time is given by... [Pg.1222]

In a 250 ml Erlenmeyer flask covered with aluminum foil, 14.3 g (0.0381 mole) of 17a-acetoxy-3j5-hydroxypregn-5-en-20-one is mixed with 50 ml of tetra-hydrofuran, 7 ml ca. 0.076 mole) of dihydropyran, and 0.15 g of p-toluene-sulfonic acid monohydrate. The mixture is warmed to 40 + 5° where upon the steroid dissolves rapidly. The mixture is kept for 45 min and 1 ml of tetra-methylguanidine is added to neutralize the catalyst. Water (100 ml) is added and the organic solvent is removed using a rotary vacuum evaporator. The solid is taken up in ether, the solution is washed with water and saturated salt solution, dried over sodium sulfate, and then treated with Darco and filtered. Removal of the solvent followed by drying at 0.2 mm for 1 hr affords 18.4 g (theory is 17.5 g) of solid having an odor of dihydropyran. The infrared spectrum contains no hydroxyl bands and the crude material is not further purified. This compound has not been described in the literature. [Pg.56]

Furthermore, one can infer quantitatively from the data in Fig. 13 that the quantum system cannot reach the maximum herringbone ordering even at extremely low temperatures the quantum hbrations depress the saturation value by 10%. In Fig. 13, the order parameter and total energy as obtained from the full quantum simulation are compared with standard approximate theories valid for low and high temperatures. One can clearly see how the quasi classical Feynman-Hibbs curve matches the exact quantum data above 30 K. However, just below the phase transition, this second-order approximation in the quantum fluctuations fails and yields uncontrolled estimates just below the point of failure it gives classical values for the order parameter and the herringbone ordering even vanishes below... [Pg.116]

We have seen that in a steady field Hq a small excess, no, of nuclei are in the lower energy level. The absorption of rf energy reduces this excess by causing transitions to the upper spin state. This does not result in total depletion of the lower level, however, because this effect is opposed by spin-lattice relaxation. A steady state is reached in which a new steady value, n, of excess nuclei in the lower state is achieved. Evidently n can have a maximum value of o and a minimum value of zero. If n is zero, absorption of rf energy will cease, whereas if n = no, a steady-state absorption is observed. It is obviously desirable that the absorption be time independent or. in other words, that s/no be close to unity. Theory gives an expression for this ratio, which is called Zq, the saturation factor ... [Pg.159]

The well-known phenomenon of smell-fatigue is explained by the theory that actual chemical reaction takes place between the odoriferous body and some reacting material in the nose thus it can easily be conceived that some sort of addition reaction takes place and that directly the osmoceptor in the nose becomes saturated no further reaction is possible and no further odour can be appreciated until fresh osmoceptor has been formed. Ruzicka has suggested that two such osmoceptors are involved since substances inspired in a concentrated state have odours different to those perceived in a dilute condition. He suggests that one osmoceptor reacts more readily than the other and in consequence is the more readily saturated or consumed, this osmoceptor is responsible for the sensation produced when dilute odours are inspired. If the odour be concentrated, the first osmoceptor is saturated almost instantaneously and then the sensation produced is the result of the reaction between the odoriferous substance and the second osmoceptor. [Pg.28]

The cooling tower cools hot water tvith cool air by countercurrent (or cross-current) fiow of the tw o fluids past each other in a tower filled with packing. This involves both mass and heat transfer. The water surface that exists on the tower packing is covered with an air film assumed to be saturated at the water temperature. The heat is transferred between this film and the main body of air by diffusion and convection. Detailed presentations of the development of cooling tower theory are given in References 39 and 46. [Pg.387]

Planck s equation, 237 for saturated vapour, 189 potential, 102 theory of radiation, 520... [Pg.542]

In an experimental wetted wall column, pure carbon dioxide, is absorbed in water. The mass transfer rate is calculated using the penetration theory, application of which is limited by the fact that the concentration should not teach more than 1 per cent of the saturation value at a depth below the surface at which the velocity is 95 per cent of the surface velocity. What is the maximum length of column to which the theory can be applied if the flowrate of water is 3 cm3/s per cm of perimeter ... [Pg.606]

A pure gas is absorbed into a liquid with which it reacts. The concentration in the liquid is sufficiently low for the mass transfer to be covered by Fick s Law and the reaction is first-order with respect to the solute gas. It may be assumed that the film theory may be applied to the liquid and that the concentration of solute gas falls from the saturation value to zero across the film. The reaction is initially carried out at 293 K. By what factor will the mass transfer rate across the interface change, if the temperature is raised to 313 K ... [Pg.630]


See other pages where Saturated theory is mentioned: [Pg.177]    [Pg.177]    [Pg.150]    [Pg.112]    [Pg.286]    [Pg.396]    [Pg.371]    [Pg.342]    [Pg.477]    [Pg.1505]    [Pg.1505]    [Pg.179]    [Pg.557]    [Pg.169]    [Pg.192]    [Pg.200]    [Pg.146]    [Pg.216]    [Pg.132]    [Pg.13]    [Pg.13]    [Pg.813]    [Pg.12]    [Pg.294]    [Pg.428]    [Pg.579]    [Pg.209]    [Pg.27]    [Pg.5]    [Pg.112]    [Pg.175]    [Pg.199]    [Pg.202]    [Pg.602]   
See also in sourсe #XX -- [ Pg.292 ]




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