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Bifurcation cascade

A bifurcation cascade with micro channels feeds a wide fixed bed (channel void space for particle insertion), followed by a multitude of catalyst retainers, which act like frits, i.e. support the catalyst particles and prevent their loss [7, 77, 78]. Besides supporting the particles, these parts have a size-exclusion function to the lower size limit of about 35-40 pm. The retainers are followed by an array of elongated channels that serve to build up a uniform pressure drop along the wide retainer bed. Finally, the streams are collected in a bifurcation cascade of identical shape as the feeding cascade, but mirror-imaged in position. [Pg.282]

GP 9] [R 16] The reaction rate and activation energy of metal catalysts (Rh, Pt or Pd) supported on alumina particles ( 3 mg 53-71 pm) were determined for conversions of 10% or less at steady state (1% carbon monoxide 1% oxygen, balance helium 20-60 seem up to 260 °C) [7, 78]. The catalyst particles were inserted into a meso-channel as a mini fixed bed, fed by a bifurcation cascade of micro-channels. For 0.3% Pd/Al203 (35% dispersion), TOF (about 0.5-5 molecules per site... [Pg.327]

This device is based on multiple parallel bi-lamination using bifurcation cascade for generating multiple thin fluid olamellae [25]. The first feed stream is split into multiple sub-streams via a bifurcation cascade in a similar way this is done for the second feed stream in another level. The corresponding sub-streams enter via nozzles into the first level. Here, the end of the channels of the bifurcation cascade and the nozzles lie next to each other. Thereby, bi-laminated sub-streams are formed and enter many parallel channels of an inverse-bifurcation cascade. These are recombined to multilayered stream in one main channel which has a serpentine shape, i.e. comprises extended length. [Pg.390]

Phosphorylation-dephosphorylation see also Period-doubling bifurcations Cascade model for mitotic oscillator, 418-44 arresting the mitotic oscillator, 438-45 double oscillator model, 448-51 extended model with autocatalysis,... [Pg.592]

Axioms 12. Movement along the bifurcation cascade in case of the system s stability loss is characterized by the movement trajectory displaying increasing the danger of a critical situation (a catastrophe) beginning. [Pg.75]

Figure C3.6.6 The figure shows tire coordinate, for < 0, of tire family of trajectories intersecting tire Poincare surface at cq = 8.5 as a function of bifurcation parameter k 2- As tire ordinate k 2 decreases, tire first subhannonic cascade is visible between k 2 0.1, tire value of tire first subhannonic bifurcation to k 2 0.083, tire subhannonic limit of tire first cascade. Periodic orbits tliat arise by tire tangent bifurcation mechanism associated witli type-I intennittency (see tire text for references) can also be seen for values of k 2 smaller tlian tliis subhannonic limit. The left side of tire figure ends at k 2 = 0.072, tire value corresponding to tire chaotic attractor shown in figure C3.6.1(a). Otlier regions of chaos can also be seen. Figure C3.6.6 The figure shows tire coordinate, for < 0, of tire family of trajectories intersecting tire Poincare surface at cq = 8.5 as a function of bifurcation parameter k 2- As tire ordinate k 2 decreases, tire first subhannonic cascade is visible between k 2 0.1, tire value of tire first subhannonic bifurcation to k 2 0.083, tire subhannonic limit of tire first cascade. Periodic orbits tliat arise by tire tangent bifurcation mechanism associated witli type-I intennittency (see tire text for references) can also be seen for values of k 2 smaller tlian tliis subhannonic limit. The left side of tire figure ends at k 2 = 0.072, tire value corresponding to tire chaotic attractor shown in figure C3.6.1(a). Otlier regions of chaos can also be seen.
At still higher energies, the elliptic island undergoes a typical cascade of bifurcations in which subsidiary elliptic islands of periods 6, 5, 4, 3 are successively created, which leads to the global destruction of the main elliptic island to the benefit of the surrounding chaotic zone. The cascade ends with a period-doubling bifurcation at Ed, above which the periodic orbit 0 is hyperbolic with reflection, and the main elliptic island has disappeared... [Pg.548]

From a physical point of view, the rhythmic phenomena are related to the fact that biological systems are maintained under far-from-equilibrium conditions through a continuous dissipation of energy [23]. However, non-equilibrium conditions can also give rise to more complicated behaviors. Chaotic dynamics, for instance, can arise either as a regular rhythmic process is destabilized and develops through a cascade of period-doubling bifurcations [24], by torus destruction in connection with the interaction of two or more rhythms, or via different types of intermittency... [Pg.35]

For this system, Venimadhavan et al. [7] have studied the bifurcation of the singular points in a reactive reboiler, while Chadda et al. [13] demonstrated the flash-cascade approach. In the present investigation, the same thermodynamic properties and kinetic expression were used (see Tab. 4 in Ref. [7]). [Pg.103]

We also now know that complex oscillations evolve as simple limit cycles become unstable, bifurcating to more complex limit cycles. Only a small number of bifurcation sequences account for all known scenarios. We have seen examples of mixed-mode sequences (H2 -I- O2) and period-doubling cascades (CO -I- O2). A third route involving quasi-periodic responses is known and arises in some chemical system [88], but has not yet been observed in combustion systems (except in some special studies in which the ambient temperature or some other parameter is forced to vary in some sinusoidal or other periodic manner [89]). The important lesson then... [Pg.539]

Experiments demonstrate that at even higher Er, the rolls become unstable and irregular. Ultimately, defect lines called disclinations form in the flow direction. As the linear analysis concerns the behavior of infinitesimal disturbances, the growth of the instability and further bifurcations are inaccessible to such analyses. This motivated Feng, Tao, and Leal to carry out a direct numerical simulation of a sheared nematic. Using the LE theory, with the one-constant approximation, they predicted a cascade of instabilities illustrated in Fig. 3. Steady state rolls first appear at Er = 2368. The director twists toward the flow (z) direction at the center of the cells. With increasing Er, the secondary flow and the director twisting intensify. [Pg.2957]

What is the relationship between cation channel opening and G protein activation during ZP3 signaling Pharmacological studies indicate that these signal transducers mediate parallel processes in a bifurcated signaling cascade. This conclusion is based on the observations that (i)ZP3 evokes cation channel-dependent membrane depolarization in pertussis toxin-treated sperm, where Gj activation... [Pg.212]

IIIC, D) Vidal, C., Bachelart, S., Rossi, A. Bifurcations in Turbulent Cascades in the Belousov-... [Pg.117]

In foods, we often have what may be called reaction cascades, i.e., a whole series of reactions, partly consecutive, partly parallel, with bifurcations and with more than one reaction pathway leading to the same product. Examples are nonenzymatic browning or Maillard reactions, as well as several changes occurring during heat treatment. Chain reactions may be involved as well, as in the formation of hydroperoxides during the autoxidation of fats ... [Pg.101]

The moment dynamics method allows us to quickly discover the bifurcation diagram. It is given in Fig. 1.22. We see that the transition from stable fixed point of the mean to spiking and back to a stable fixed point is exceptionally complicated. We see a period-doubling cascade followed by a Canard explosion of the chaotic attractor, then a reverse period adding sequence towards a state of uninterrupted spiking. At higher noise inten-... [Pg.36]


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See also in sourсe #XX -- [ Pg.282 ]

See also in sourсe #XX -- [ Pg.135 ]




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Bifurcate

Bifurcated

Bifurcation Analysis of the Flash Cascade Model

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