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Intermediate region

For particles with y < 0.67, the correlations of Becker Can. J. Chem. Ertg., 37, 85-91 [1959]) should be used. Reference to this paper is also recommended for intermediate region flow. Setthng charac teristics of nonspherical particles are discussed by Clift, Grace, and Weber, Chaps. 4 and 6. [Pg.678]

The curves in Fig. 15-5 are greatly simplified and only apply to one instant of time. In practice there are always several trams with varying current draw on a stretch of track. Currents and potentials are then subjected to wide time-dependent variations. Without protective measures, the pipe/soil potentials are usually always more negative in the outer regions of a tramway system and more positive in the vicinity of the transformer substation. In a wide intermediate region, potential changes occur in both directions. The current entrance and exit areas can be deter-... [Pg.359]

Exploration of the region 0 < T < requires numerical calculations using eqs. (2.5)-(2.7). Since the change in /cq is small compared to that in the leading exponential term [cf. (2.14) and (2.18)], the Arrhenius plot k(P) is often drawn simply by setting ko = coo/ln (fig. 5). Typical behavior of the prefactor k and activation energy E versus temperature is presented in fig. 6. The narrow intermediate region between the Arrhenius behavior and the low-temperature limit has width... [Pg.15]

Friction also changes the way k ) approaches its low-temperature limit and widens the intermediate region between the two asymptotes of k(P). At temperatures far below the cross-over point k T) behaves as... [Pg.19]

It is to be emphasized that, despite the formal similarity, the physical problems are different. Moreover, in general, diabatic coupling is not small, unlike the tunneling matrix element, and this circumstance does not allow one to apply the noninteracting blip approximation. So even having been formulated in the standard spin-boson form, the problem still remains rather sophisticated. In particular, it is difficult to explore the intermediate region between nonadiabatic and adiabatic transition. [Pg.92]

The results for the tunneling splitting calculated with the use of some of the earlier proposed reaction paths for a single PES (4.40) (with the parameters adopted here) are collected by Bosch et al. [1990]. All of them underestimate by at least an order of magnitude the numerically exact value 10.6 cm which is also given in that paper. The parameters C and Q hit the intermediate region between the sudden and adiabatic approximations, described in sections 2.5 and 4.2, and neither of these approximations is quantitatively applicable to the problem. [Pg.99]

An Arrhenius plot of the rate constant, consisting of the three domains above, is schematically shown in fig. 45. Although the two-dimensional instanton at Tci < < for this particular model has not been calculated, having established the behavior of fc(r) at 7 > Tci and 7 <7 2, one is able to suggest a small apparent activation energy (shown by the dashed line) in this intermediate region. This consideration can be extended to more complex PES having a number of equivalent transition states, such as those of porphyrines. [Pg.108]

The major advantage of a mobile monitoring system is its ability to obtain air quality information in the intermediate region between source monitors... [Pg.218]

The skimmer has a smaller aperture than the sample cone, which creates a pressure of 10 atmospheres in the intermediate region. The ions are conducted through the cones and focused into the quadrupole with a set of ion lenses. Much of the instrument s inherent sensitivity is due to good designs of these ion optics. [Pg.627]

In the general case, a buoyant jet has an initial momentum. In the region close to discharge, momentum forces dominate the flow, so it behaves like a nonbuoyant jet. There is an intermediate region where the influence of the initial momentum forces becomes smaller and smaller. In the final region, the buoyancy forces completely dominate the flow and it behaves like a plume. When the jet is supplied at an angle to the vertical direction, it is turned upward by the buoyancy forces and behaves virtually like a vertical buoyant jet in a far field. A negative buoyant jet continuously loses momentum due the opposite direction of buoyancy forces to the supply air momentum and eventually turns downward. [Pg.456]

Between the nonbuoyant jet region and the plume region lies an intermediate region in which the flow changes from the former to the latter.The axial location of the beginning of this intermediate region depends primarily on the exit Froude number ... [Pg.456]

The importance of the triples contribution with QCISD theory is clearly illustrated in the enlargement. The QCISD curve is very near the MP4 curve. The authors of the paper from which this exercise is drawn emphasized the importance of the single and triples to the MP4 level, but nevertheless concluded that MP4(SDTQ) was not an adequate representation of the potential energy surface in the intermediate region... [Pg.189]

The spin contamination makes the UCC energy curves somewhat too high in the intermediate region, but the infinite nature of coupled cluster methods makes them significantly better at removing unwanted spin states as compared to UMPu methods (Figure 11.8). [Pg.282]

The corresponding curves based on a UHF reference are shown in Figure 11.13. It is immediately clear that DFT methods do not have the spin contamination problem in the intermediate region, indeed spin contamination is not well defined in DFT." Removing the spin contamination by projection methods gives rise to discontinuous derivatives and artificial minima, analogously to the PUFIF case in Figures 11.3 and... [Pg.283]

The Dissociation Constant of Nitric Acid. The largest value of K in Table 9 is that for the (HS04) ion. In Fig. 36 there is a gap of more than 0.2 electron-volt below the level of the (H30)1 ion. As is well known, several acids exist which in aqueous solution fall iu the intermediate region between the very weak acids and the recognized strong acids the proton levels of these acids will fall in this gap. The values of K for these acids obtained by different methods seldom show close agreement. Results obtained by various methods were compared in 1946 by Redlich,1 who discussed the difficulties encountered. [Pg.138]

In the intermediate region both terms have to be used. Therefore, the superficial velocity at minimum fluidising conditions can be found by combining (17.7.2.2) and (17.7.2.3) and multiplying both sides by pd lfi2 (1 — emf) to yield ... [Pg.399]

Wittwer and Zollinger (1954) determined the neutralization curves of aqueous solutions of diazonium salts under standard conditions of ionic strength, etc., and found that the acidity depended on the degree of neutralization in a manner different to that expected for a dibasic acid. The curve obtained did not exhibit two steps with an intermediate region of a few pH units in which the monobasic acid is stable, as is the case, for instance, with oxalic acid (Fig. 5-1). On the contrary, there was only one step, but it extended over two equivalents of base per diazonium ion. [Pg.90]

Each of the curves in Figure 5-3 exhibits two or three pH regions in which the slope of the logarithmic plot is approximately —1, with intermediate regions where the slope is small or zero. Lewis and Hanson (1967) showed that in the case of (E,)-4-nitrobenzenediazoate the portion of the curve with slope —1 at relatively high pH was consistent with the acidity constant K3 of the (E )-diazohydroxide determined either by titration or spectrophotometrically, the relevant results being (by... [Pg.101]

In both models the rotational shift of the line 5co is the same either in the static limit, where it is equal to zero, or in the case of extreme narrowing where it reaches its maximum value coq. A slight difference in its dependence on tE is observed in the intermediate region only. The experimentally observed density dependence of the shift shown in Fig. 3.5 is in qualitative agreement with theory. [Pg.104]

The analysis performed allows one to judge qualitatively about the processes, which go on in a spectrum when the Stark structure of rotational transitions is averaged by fluctuations of the orienting field. If y decreases, x being fixed, the resolved Stark structure with the intense Q-branch in the centre transforms into the spectrum of a quasi-free rotator. If x < 1, the spectrum may be singlet in the intermediate region. [Pg.240]

As mentioned in Section 21.4.1, the existence of intermediate phase with slightly stiffer modulus than that of mbber matrix was reported, which was determined by finite element calculation. The author reported that there are two phases around CB—one is almost comparable with bound mbber, 2 nm-thick glassy phase (GH-phase), another is 10 nm-thick uncross-Unked one (SH-phase). The intermediate regions in this smdy were usually observed around CB regions and the Young s modulus of this region was higher as well. Thus, there is a possibility that SH-phase was directly observed in real space for the first time. [Pg.602]

There are a number of industrial and technological areas in which nanoscale adhesion is important. One of the earliest fields concerned with adhesion on this scale was colloid science. Colloid particles lie in the intermediate region between macro and nano, with dimensions typically of the order of hundreds of nanometers up to a few microns. This means that their true contact areas he well within the nano-domain and are influenced by interactions on this length scale. Adhesion between such particles is important, due to its influence on mineral separation processes and on the aggregation of powders, for example, on the walls of machinery or in the forming of medical tablets. In an extraterrestrial context, such... [Pg.17]


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See also in sourсe #XX -- [ Pg.321 ]




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