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Steady state relation

Carry out simulations for differing tank volumes, flow rates and feed concentrations, in which the inlet and outlet flow rates are set equal, (F + P2 = F3) and observe the approach to steady state. Relate the time taken to approach steady state to the mean tank residence time (t = V/F3). [Pg.494]

The rate of a liquid phase reaction is governed by diffusion to and adsorption on the surface of the catalyst. The steady state relation is... [Pg.724]

Hence, (VIII-46) is the rate determining step of ozone destruction. From (VIII-45) to (VII1-47) we obtain the following steady state relation for NO and N02... [Pg.113]

Fig. 6.3 Steady state relation between the metabolite S normalized by the value, Si, = vmaxGKf/b and the glucose concentration, G, for different values of the maximal active fraction Xmax. The smallest active fraction value, Xq, is set equal to 0.1. The main effect of the translocation of glucokinase is a right hand shift of the relation, resulting in a threshold value forthe glucose sensor. Fig. 6.3 Steady state relation between the metabolite S normalized by the value, Si, = vmaxGKf/b and the glucose concentration, G, for different values of the maximal active fraction Xmax. The smallest active fraction value, Xq, is set equal to 0.1. The main effect of the translocation of glucokinase is a right hand shift of the relation, resulting in a threshold value forthe glucose sensor.
Here, max and jrm n denote, respectively, the maximum and the minimum values of the muscular activation, a determines the slope of the feedback curve, S is the displacement of the curve along the flow axis, and Fneno is a normalization value for the Henle flow. The relation between the glomerular filtration and the flow into the loop of Henle can be obtained from open-loop experiments in which a paraffin block is inserted into the proximal tubule and the rate of glomerular filtration (or, alternatively, the so-called tubular stop pressure at which the filtration ceases) is measured as a function of an externally forced rate of flow of artificial tubular fluid into the loop of Henle. Translation of the experimental results into a relation between muscular activation and Henle flow is performed by means of the model, i.e., the relation is adjusted such that it can reproduce the experimentally observed steady state relation. We have previously discussed the significance of the feedback gain a in controlling the dynamics of the system, a is one of the parameters that differ between hypertensive and normotensive rats, and a will also be one of the control parameters in our analysis of the simulation results. [Pg.323]

This quantity is independent of the index k because, for the present development, we are ignoring any effects of the space charge. [From eqn. (37), we see that Ek = E0 for all values of k when the space charge is negligible]. Equation (119) above likewise yields Jfe + 1 merely by replacing k by k + 1 in the three places where it occurs. Thus substituting eqn. (119) into the steady-state relation given by eqn. (118) yields... [Pg.49]

For spherical symmetry we note that Jv4m2 is constant in the steady state, where Am2 is the area of a sphere. As concentric spherical shells of water thus move toward the sphere, the flux density increases inversely as r2. We thus obtain the following steady-state relation describing the volume flux density Jv at distance r from the center of a sphere when Jv varies only in the radial direction and LSDl1 is constant ... [Pg.467]

Here the species Y is taken to be CO and the new quadratic termination step is reaction (cii). The system is reduced to a binary one in [O] and [CO ] by introducing the steady state relations for [H] and [OH] only. Analysis along the lines indicated above then predicts the three types of behaviour (i) no reaction (or very slow reaction controlled by initiation) when 0 < 0 (ii) damped oscillation or a sustained glow when 0 > 0 but less than some critical value and (iii) explosive behaviour when 0 is greater than the critical value. The distinctive difference from the hydrogen oxidation system, where there is a sharp transition from slow reaction to explosion at 0 = 0, is that now there is a more gradual transition within the region 0 < 0 < fep. This is in accord with the experimental observations [511]. [Pg.233]

The mechanism, then, consists of Reactions 1-14 in Table I and includes the following species NO, NO2, O3, HC, O, OH, HOo, ROo-, HNO2, HNO3, RCHO, and PAN. Differential equations are required for the first four species, steady state relations for the next five. The last three species are products and may also be represented by differential... [Pg.79]

Evans and Searles reviewed the transient fluctuation relations, how steady state relations can be derived from them, their implications and applications, and experimental tests available in 2002. A shorter review paper highlighted the main results, and a derivation of the second law inequality. Recently, Sevick et al reviewed the ES FR, the Crooks FR and the Jarzynski equality, highlighting the similarities and differences between the two FRs and also discussing experimental work that has been carried out to test these results. [Pg.183]

However, despite numerical, and recent experimental evidence, that the steady state relation does hold under these assumptions, it must be said that there are some subtleties regarding convergence times and the decay of fluctuations in nonequilibrium steady states. Recently a much more rigorous derivation of the steady state ES FR has been given. This derivation demonstrated that the underlying assumption necessary to obtain (2.4) is that time-correlations decay sufficiently quickly. ... [Pg.186]

Recently, Douarche et al verified the transient ES FR and steady state ES FR for a harmonic oscillator (a brass pendulum in a water-glycerol solution, that is driven out of equilibrium by an applied torque). They also developed a steady state relation for a system with a sinusoidal forcing, and showed that the convergence time was considerably longer in this case. [Pg.190]

The flow-through system need provide only a single sampling point for liquid which is regarded as being in a steady state relation with the crystallizing solid. Another version of the Doemer-Hoskins equation provides a relationship between the concentrations of the trace elements in the flowing liquid and the crystalline solid which has just been deposited from it. [Pg.161]

It should be noted that the model predicts arc volcanic fluxes that are currently too low. This occurs because, in our model, the steady-state relation between the mid-ocean ridge flux and Fare is Farc/T ridge (1 L deep)/L deep For Cdeep —... [Pg.252]

In derivation of the steady state relations, artificial, reversible thermostats such as the Gaussian thermostat or Nose-Hoover thermostat have been used. However, Williams et al.22S have recently used MD simulations to verify assumptions made in their derivation that shows that the FR is insensitive to the details of the thermostatting mechanism. [Pg.350]

The steady-state relation between cell mass and dilution rate is obtained by combining Eqs. (5-9) ... [Pg.60]

B = steady states related to the plateau and baseline S and W = sampling arm in the sample and blank solution cups a = lag phase two.s = half wash time. Adapted from Anal. Chim. Acta 78 (1975) 145, J. Ruzicka, E.H. Hansen, Flow Injection Analyses. Part I. A new concept of fast continuous flow analyses, with permission from Elsevier (Ref. [6]). [Pg.151]

If the rate of surface reaction is not much smaller than the rate of adsorption, then a steady non-equilibrium treatment may be employed. For unimolecular reaction, this steady state relation is given... [Pg.27]

FIGURE 3 Effect of changes in phosphatase rate on the steady-state relation between force and phosphorylation in swine carotid artery according to the Hai and Murphy four-state model. The rate constants for phosphatase activity (kj and k ) were varied over a 50-fold range from 0.1 s (dotted line) to 5 s (dashed line). The rate constants for kinase activity (kj and k ) were varied to produce the desired range of phosphorylation. All other constants (kj and k4, and ky) were consistent with the original Hai and Murphy formulation. [Pg.348]

The use of a second downstream electrode to monitor chemical fluxes at the working electrode is proving to be an important technique for the investigation of electrode mechanisms. This is particularly true for electrodes which have a more complicated structure than a simple metallic surface. Examples are modified electrodes, oxide electrodes, or enzyme electrodes. For these more complex systems, the separate measurement of the fluxes at the electrolyte-electrode interface provides unique and valuable information. Double electrodes can be constructed for all three hydrodynamic systems. A crucial parameter for such a double electrode is the collection efficiency, N, which, in the steady state, relates the flux of material detected as a limiting current on the downstream electrode to the flux of material generated on the upstream electrode. The collection efficiency is a function of the geometry of the electrode and is given for all three systems by [4, 9]... [Pg.133]

Chuang and Han [1984] reported that for miscible and immiscible blends at constant composition, the plots of Nj vs. 0 2 and G vs. G are independent of T. However, while for single phase systems the two dependencies are approximately parallel, for immiscible blends, such as PS/PMMA, the steady state relation may be quite different from the dynamic one. [Pg.519]

Note again that the O atom concentration in the lower stratosphere is too low for reaction 4.31 to compete effectively with reaction 4.34.) According to this steady-state relation, decrease in [NO2] leads to an increase in [CIO]. In situ measurements exhibit this behavior and show that CIO mixing ratios range between 10 and 70 ppt depending on the level of NO2. [Pg.188]

The behavior of HO2 and OH in the upper troposphere is dominated by CO chemistry. (Because of its 1 to 3 month lifetime, CO is more or less uniformly mixed up to the tropopause. Above the tropopause, CO falls off with increasing altitude. Because of the much slower vertical transport rate in the stratosphere, the rate of the CO-OH reaction competes with the rate of vertical mixing.) Tropospheric CO oxidation proceeds according to reactions 5.24 and 5.25, coupled to reactions 5.1 to 5.3. (Note that 4.36 and 5.25 are the same reaction.) From Section 5.2 we can obtain an expression for the HO2/OH ratio in the upper troposphere. Based on the steady-state relation for HO2, we obtain... [Pg.263]

Given that the steady-state concentrations of the four receptor forms are nonlinear functions of the amplitude of the stimulus, we would expect that different values of L, give rise to different redistributions of the receptor between the forms R, D, X and Y, so that, at steady state, relation (8.1) would give a value for the activity that would differ from the basal value, Aq. In conformity with intuition, this phenomenon indeed occurs in the general case and corresponds to partial adaptation (fig. 8.7, curves b and c). It is, however, possible to show (Segel et al.,... [Pg.316]

Figure 11.6-3 Region of multiple steady states. Relation between Peclet, Damkohler, and fiy group after Hlavacek and Hofmann [60]). [Pg.531]

A MIMO control system must be configured for the retrofitted column. To compute the RGA, a linearized model, in the steady state, relates the changes in the designated outputs, T, L, and Li, to those of the manipulated variables, gi, Q2, and S ... [Pg.717]


See other pages where Steady state relation is mentioned: [Pg.135]    [Pg.153]    [Pg.156]    [Pg.156]    [Pg.97]    [Pg.493]    [Pg.90]    [Pg.1151]    [Pg.248]    [Pg.160]    [Pg.196]    [Pg.19]    [Pg.57]    [Pg.59]    [Pg.15]    [Pg.218]   
See also in sourсe #XX -- [ Pg.153 , Pg.156 ]




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Second-Law Relation for Steady-State Flow Processes

States Relations

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