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Transitional conditions

Models and theories have been developed by scientists that allow a good description of the double layers at each side of the surface either at equilibrium, under steady-state conditions, or under transition conditions. Only the surface has remained out of reach of the science developed, which cannot provide a quantitative model that describes the surface and surface variations during electrochemical reactions. For this reason electrochemistry, in the form of heterogeneous catalysis or heterogeneous catalysis has remained an empirical part of physical chemistry. However, advances in experimental methods during the past decade, which allow the observation... [Pg.307]

The matter of predicting flow pattern transitions is still in a developing state. In some cases the transition mechanisms are reliably understood, other mechanisms suggested are more in the nature of speculations.. .. If the ability to predict these transition conditions is to become more reliable and more generalized, it will require considerable additional research into mechanisms and into the basic fluid mechanical factors that enter into these mechanisms. [Pg.160]

Consequently, kuo (ML-3 "1) is equal to Yt l for [j] KiM. In both of these limiting cases, and obviously for the transitional conditions between, we need information on the factors quantifying microbial growth, pmax, KM, and Y and on the abundance of cells, [B]t, to be able to predict transformation rates of the compound when it limits population growth (see Illustrative Example 17.6 on page 747). [Pg.744]

Therefore the electronic structure of a transitive condition determining SN2 replacement of halogen in halogen substituted compaunds with participation aniona (II) is considered. In a case methylbromid and benzylbromid reaction goes on to the circuit 1. [Pg.80]

At the interfaces between the media, the tangential component of Ey as well as the tangential component of Hy needs to be continuous. These transition conditions result in a set of linear equations which only yield nontrivial solutions if the coefficient determinant vanishes, and we get the eigenvalue ... [Pg.30]

Their data indicate that the flow transition from gas-continuous to pulsed flow occurs at higher- gas and liquid flow rates for nonwettable solids compared to wettable solids. The change in transition condition due to solids wettability occurs because a major fraction of the liquid tends to flow as rivulets over the nonwettable surface and, thus, delays the formation of a liquid film capable of blocking the interstices between the particles. Furthermore, an increase in bed porosity will also move the transition to occur at higher gas and liquid flow rates. [Pg.182]

A description consistent with NET is the Maxwell-Stefan equations. In the application of Maxwell-Stefans equations, one frequently neglects the heat of transfer, q This assumption may be good for gases. It is not so good for liquid mixtures. According to Section 3, it is likely that the heat of transfer plays an important role in flux equations of interface transport. Olivier showed that failure to include the heat of transfer leads to an error of up to 20% in the heat flux calculated for some typical phase transition conditions. [Pg.5]

Here Ho + Htun is the small polaron Hamiltonian, Hg describes the correlation between the carriers and the applied field S Hg is the operator describing intraband transitions conditioned by fight absorption, E is the carrier coupling... [Pg.417]

A shortcoming is the instability against external conditions, in particular, temperature. To induce a phase transition with a minimum amount of photochemical change, the molecular aggregate system should be placed close to the phase transition condition. Consequently, the operative temperature range is rather limited. [Pg.438]

These maps are to satisfy an obvious transitivity condition and... [Pg.107]

Thus, besides the Eqs. (4), (5) and (8), the known steady-state thermo-hydrodynamic correlations of the LHP should be also implemented to the model. The necessity of such mutual consideration appears obvious in case of determining transition conditions from the thermal mode 2 to the thermal mode 3, and in the analysis of heat transfer regularities of the thermal mode 3. Assuming that vapor channel length Lych is independent on the heat supply, the following equation yields a dependency between the curvature radius and surface area of the vapor-liquid interface ... [Pg.129]

For practical spray heat transfer calculations, a summary of empirical and interpolation correlations for each regime of spray boiling curve, ranging from single-phase to film boiling, and of transition conditions between these regimes has been provided [139,140]. As an illustration of how the hydrodynamic and other parameters affect heat transfer to sprays, the empirical equation for the critical heat flux q"cw is provided as an example [139] ... [Pg.1435]

For each special problem, the Maxwell equations are used with their limiting and transition conditions and numerical solutions of these equations are tried. [Pg.434]

Hydrogen at the surface of Mg particles is considered to exist instantaneously in the form Mg-2(H ) when the reaction proceeds under transitional conditions where the temperature and pressure conditions are transferred from hydrogenation to dehydrogenation regions by a rapid increase in temperature at a constant rate. [Pg.134]

From the start-up operations of plantation establishment to the attainment of steady state, transition conditions prevail with respect to nutrients. In this case, the amount of organic material decomposed will not be equal to the annual organic inputs. Transition-period fertilizer requirements are estimated in conjunction with start-up operation requirements and costs. They will be larger than steady-state requirements since full credit for the organic inputs cannot be taken each year. [Pg.511]

Formation of trans-structure at heats speaks thermal isomerization. The alternative opportunity trans-disclosing of triple bond in a catalytic complex for a transitive condition is forbidden spatially [22, 23], The structure of a complex and a kinetics of polymerization are considered in works in more detail [14, 24],... [Pg.88]

Fisher concluded that the above values of the loop class exponent c intjply a continuous phase transition in d = 2 tuid d = 3. In [89] it is shown that the phase transition condition is satisfied in both d = 2 tuid in d = 3 for the case when the double stranded segments are treated as straight paths. Note that in d = 2, self-avoiding walks as paths will result in no phase transition. [Pg.93]

In oxidative epoxidation reactions besides of oxidizing agent often various catalysts systems are used [14]. It was established that the rate of heterolytic decomposition of 0-0 bonds in tertiary-butyl peroxide in the presence of catalysts such as Mo(CO)g proceeds in result of complexation between metal and hydroperoxide. By the authors suggested the probable schemes transition condition, without discussion of valent state of metal (Scheme 2). [Pg.283]


See other pages where Transitional conditions is mentioned: [Pg.162]    [Pg.164]    [Pg.39]    [Pg.43]    [Pg.274]    [Pg.323]    [Pg.210]    [Pg.211]    [Pg.165]    [Pg.81]    [Pg.81]    [Pg.82]    [Pg.184]    [Pg.290]    [Pg.380]    [Pg.246]    [Pg.1457]    [Pg.264]    [Pg.437]    [Pg.27]    [Pg.262]    [Pg.386]    [Pg.89]    [Pg.92]    [Pg.680]    [Pg.131]    [Pg.129]    [Pg.23]    [Pg.307]    [Pg.332]    [Pg.71]    [Pg.283]   
See also in sourсe #XX -- [ Pg.274 ]




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