Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Intermediate law range

Viscosity affects the various mechanisms of separation in accordance with the appropriate settling law. Tor instance, viscosity has no effect on terminal velocities in the range where Newton s law applies except as it affects the Reynolds Number which determines which settling law applies. Viscosity does affect the terminal velocity in both the Intermediate law range and Stokes law range as well as help determine the Reynolds Number. As the pressure increases or the temperature decreases the viscosity of the gas increases. Viscosity becomes a large factor in very small particle separation (Intermediate and Stokes law range). [Pg.90]

This rate law has been observed for GaAs/Fe2+ in strongly acidic aqueous medium [57], see Fig. 4 as an example, for GaAs/Fe(II)-EDTA in the intermediate pH range [50], and for GaAs/TMPD in acidic aqueous medium at high LiCl concentrations [58], as well as in 42 mol% CH3CN-58 mol% H2O [55]. [Pg.14]

Since 3.3 < 5.39 < 43.6, the intermediate law is valid for the larger particle size. Therefore, the particle size range is... [Pg.299]

Other than PEB-11, in addition to the low temperature power law behavior, a correlation peak evolves at aroimd Q = 0.025 A . For the intermediate temperature range (between 40 and 20 °C), a Q behavior at low Q appears. The low-Q Porod scattering indicates formation of large aggregates featuring a weU-defined surface, while its attenuation with decreasing tern-... [Pg.67]

Using these expressions for Upzt for the intermediate region and the Newton s law range, one can etisily develop expressions for the particle size corresponding to the critical settling velocity, f/, = Vz, as well as the case of equalsettling particles. Considerable complexity, however, will be encountered in determining Upzt in concentrated suspensions. [Pg.375]

The reversible homolysis of 8 (Scheme 4.6) and the reversible reactions between the dormant and active chains in the NMP (Scheme 4.5) are similar reactions obeying the same kinetic laws. The only difference is that the starting alkoxyamine R R NOR is rapidly transformed into the macroalkoxyamines R R N0M R (dormant chains) and at the end of the process into the final polymer R R NOMpR. If the conversion of monomer occurs within the intermediate time range (Figure 4.1), the result will be the living and controlled polymer R R NOMpR contaminated with only small amounts of free nitroxide R R NO and dead chains resulting from significantly diminished termination reactions. [Pg.139]

In the intermediate concentration ranges in Figure 7.5, we see that the fugacity of species a in the liquid phase is between the two limiting cases given by the Lewis/ Randall rule and Henry s law. We expect this behavior because, at intermediate concentrations, molecule a sees some other a molecules (characteristic of the Lewis/Randall rule) and some b molecules (characteristic of Henry s law). Thus, the fugacity of species... [Pg.415]

Mechanisms. Mechanism is a technical term, referring to a detailed, microscopic description of a chemical transformation. Although it falls far short of a complete dynamical description of a reaction at the atomic level, a mechanism has been the most information available. In particular, a mechanism for a reaction is sufficient to predict the macroscopic rate law of the reaction. This deductive process is vaUd only in one direction, ie, an unlimited number of mechanisms are consistent with any measured rate law. A successful kinetic study, therefore, postulates a mechanism, derives the rate law, and demonstrates that the rate law is sufficient to explain experimental data over some range of conditions. New data may be discovered later that prove inconsistent with the assumed rate law and require that a new mechanism be postulated. Mechanisms state, in particular, what molecules actually react in an elementary step and what products these produce. An overall chemical equation may involve a variety of intermediates, and the mechanism specifies those intermediates. For the overall equation... [Pg.514]

Kinetic studies involving enzymes can principally be classified into steady and transient state kinetics. In tlie former, tlie enzyme concentration is much lower tlian that of tlie substrate in tlie latter much higher enzyme concentration is used to allow detection of reaction intennediates. In steady state kinetics, the high efficiency of enzymes as a catalyst implies that very low concentrations are adequate to enable reactions to proceed at measurable rates (i.e., reaction times of a few seconds or more). Typical enzyme concentrations are in the range of 10 M to 10 ], while substrate concentrations usually exceed lO M. Consequently, tlie concentrations of enzyme-substrate intermediates are low witli respect to tlie total substrate (reactant) concentrations, even when tlie enzyme is fully saturated. The reaction is considered to be in a steady state after a very short induction period, which greatly simplifies the rate laws. [Pg.833]

FIG. 34 (a) Log-log plot of i ads(0 ane for an adsorbed layer containing 64 chains (cf) = 0.25), where at time / = 0 the adsorption energy strength e is reduced from e = -4.0 to values between e = -1.2 and e = -0.2, as indicated in the figure. Straight lines show a power law Fads(t) oc over some intermediate range of times. The inset shows that the (effective) exponent a can be fitted to a linear decrease with e. (b) The same data but with the equilibrium part ads(l l) subtracted [23]. [Pg.622]

The Warner function has all the desired asymptotical characteristics, i.e. a linear dependence of f(r) on r at small deformation and a finite length Nlp in the limit of infinite force (Fig. 3). In a non-deterministic flow such as a turbulent flow, it was found useful to model f(r) with an anharmonic oscillator law which permits us to account for the deviation of f(r) from linearity in the intermediate range of chain deformation [34] ... [Pg.85]

In Mampel s treatment [447] of nucleation and growth reactions, eqn. (7, n = 3) was found to be applicable to intermediate ranges of a, sometimes preceded by power law obedience and followed by a period of first-order behaviour. Transitions from obedience of one kinetic relation to another have been reported in the literature [409,458,459]. Equation (7, n = 3) is close to zero order in the early stages but becomes more strongly deceleratory when a > 0.5. [Pg.61]

As can be seen from the above, the shape of the resolved rotational structure is well described when the parameters of the fitting law were chosen from the best fit to experiment. The values of estimated from the rotational width of the collapsed Q-branch qZE. Therefore the models giving the same high-density limits. One may hope to discriminate between them only in the intermediate range of densities where the spectrum is unresolved but has not yet collapsed. The spectral shape in this range may be calculated only numerically from Eq. (4.86) with impact operator Tj, linear in n. Of course, it implies that binary theory is still valid and that vibrational dephasing is not yet... [Pg.193]


See other pages where Intermediate law range is mentioned: [Pg.273]    [Pg.273]    [Pg.273]    [Pg.275]    [Pg.79]    [Pg.257]    [Pg.273]    [Pg.273]    [Pg.273]    [Pg.275]    [Pg.79]    [Pg.257]    [Pg.224]    [Pg.37]    [Pg.59]    [Pg.59]    [Pg.323]    [Pg.14]    [Pg.462]    [Pg.1110]    [Pg.532]    [Pg.863]    [Pg.162]    [Pg.223]    [Pg.375]    [Pg.212]    [Pg.173]    [Pg.287]    [Pg.393]    [Pg.314]    [Pg.160]    [Pg.220]    [Pg.196]    [Pg.202]    [Pg.411]    [Pg.263]    [Pg.7]    [Pg.158]    [Pg.221]    [Pg.242]    [Pg.824]    [Pg.315]   
See also in sourсe #XX -- [ Pg.28 , Pg.273 , Pg.275 , Pg.279 , Pg.285 , Pg.576 ]




SEARCH



Intermediate law

Intermediate range

© 2024 chempedia.info