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Nonlinearity factors

Table IV gives minimum steam requirement (infinite stages) at several different solution capacities. The factor attribu-able to equilibrium nonlinearity increases as more SO2 is absorbed, because the buffer capacity is consumed to a greater extent. Any capacity for SO2 absorption can be achieved by varying Na concentration (pH) in the solution. At low pH ([Na] = 1.5 M) the solution capacity for SO2 absorption is small, but the nonlinearity factor is also small (1.05). Solution capacity can be increased by operating at higher pH ([Na] = 2.5 M), but nonlinearity is more severe (1.32). Table IV gives minimum steam requirement (infinite stages) at several different solution capacities. The factor attribu-able to equilibrium nonlinearity increases as more SO2 is absorbed, because the buffer capacity is consumed to a greater extent. Any capacity for SO2 absorption can be achieved by varying Na concentration (pH) in the solution. At low pH ([Na] = 1.5 M) the solution capacity for SO2 absorption is small, but the nonlinearity factor is also small (1.05). Solution capacity can be increased by operating at higher pH ([Na] = 2.5 M), but nonlinearity is more severe (1.32).
Na](M) pS02/pH20 0.02, infinite stages Steam Requirement Moles H20/Mole SO2 90% SO2 removal,, 1.0 M Citrate Nonlinearity Factor Capacity Moles S02/liter... [Pg.289]

One theory that describes the temperature dependence of relaxation time and structural recovery is the Tool-Narayanaswamy-Moynihan (TNM) model developed to describe the often nonlinear relationship between heating rate and Tg. In this model, the structural relaxation time, x, is referenced as a function of temperature (T), activation enthalpy (Ah ), universal gas constant (R), hctive temperature (7)), and nonlinearity factor (x) (Tool, 1946 Narayanaswamy, 1971 Moynihan et al., 1976) ... [Pg.795]

Since V-V transfer is in general much more efficient than V-T transfer, all these experiments were performed with a low concentration of vibrational energy acceptor molecules to slow down the transfer rate to an experimentally accessible value. This already rules out any possibility of observing three-body interference effects [Eq. (31)]. Most experiments have been performed at only a single temperature and density in the liquid, which makes detailed quantitative analysis difficult. But nevertheless comparison of these results with available gas-phase data at the same temperature (but unfortunately not the same sample) gives generally an experimental nonlinearity factor g around 1 (see Table II). [Pg.318]

Figure 3.6. Network architecture for determination of / nonlinear factors using an autoassociative neural network, a indicates nodes with sigmoidal functions, indicates nodes with sigmoidal or linear functions [150]. Figure 3.6. Network architecture for determination of / nonlinear factors using an autoassociative neural network, a indicates nodes with sigmoidal functions, indicates nodes with sigmoidal or linear functions [150].
If the primary aim is to characterize the nonlinear absorption, several direct techniques are more easily implemented or interpreted. Conceptually, the simplest technique is to measure the transmitted intensity as a fimction of the incident intensity on the sample. Separating the linear and nonlinear contributions depends upon the spatial and temporal characteristics of the laser, however, as well as the thickness L and reflectivity R of the sample surfaces. For example, if the laser provides a CW beam of uniform spatial intensity, normally incident on a sample, the transmission T may be expressed as a product T = TlTVi, of the linear transmission Tl = (1-R ) and a nonlinear factor = l/d + f)... [Pg.5134]

Due to major computational difficulties, nonlinear configuration models have not been frequently encountered in the supply chain configuration literature (see Wu and O Grady (2004) for a brief discussion of nonlinear programming models in supply chain configuration). The main nonlinear factors relevant to supply chain configuration, such as inventory and transportation costs, are usually represented using piece-wise linear functions (e.g., Tsiakis et al. 2001). [Pg.165]

Originally, Miles and Munk believed that their harbor paradox concept was valid for every harbor mode provided the corresponding spectral peak was sharp and well defined. Further thorough examination of this effect indicated that the harbor paradox is only of major importance for the Helmholtz mode, while for higher modes frictional and nonlinear factors, not accounted for in the theory. [Pg.207]

In the nonlinear range the dependence on the level of the applied load can be expressed by multiplying the linear parameters by so-called nonlinearity factors which, of course, are load-, time- and temperature-dependent [22,23]. The... [Pg.397]

The applications of this simple measure of surface adsorbate coverage have been quite widespread and diverse. It has been possible, for example, to measure adsorption isothemis in many systems. From these measurements, one may obtain important infomiation such as the adsorption free energy, A G° = -RTln(K ) [21]. One can also monitor tire kinetics of adsorption and desorption to obtain rates. In conjunction with temperature-dependent data, one may frirther infer activation energies and pre-exponential factors [73, 74]. Knowledge of such kinetic parameters is useful for teclmological applications, such as semiconductor growth and synthesis of chemical compounds [75]. Second-order nonlinear optics may also play a role in the investigation of physical kinetics, such as the rates and mechanisms of transport processes across interfaces [76]. [Pg.1289]

These quartic equations are solved in an iterative maimer and, as such, are susceptible to convergence difficulties. In any such iterative process, it is important to start with an approximation reasonably close to the final result. In CC theory, this is often achieved by neglecting all of tlie temis tliat are nonlinear in the t amplitudes (because the ts are assumed to be less than unity in magnitude) and ignoring factors that couple different doubly-excited CSFs (i.e. the sum over i, f, m and n ). This gives t amplitudes that are equal to the... [Pg.2178]

We have encountered oscillating and random behavior in the convergence of open-shell transition metal compounds, but have never tried to determine if the random values were bounded. A Lorenz attractor behavior has been observed in a hypervalent system. Which type of nonlinear behavior is observed depends on several factors the SCF equations themselves, the constants in those equations, and the initial guess. [Pg.194]

Adaptive Control. An adaptive control strategy is one in which the controller characteristics, ie, the algorithm or the control parameters within it, are automatically adjusted for changes in the dynamic characteristics of the process itself (34). The incentives for an adaptive control strategy generally arise from two factors common in many process plants (/) the process and portions thereof are really nonlinear and (2) the process state, environment, and equipment s performance all vary over time. Because of these factors, the process gain and process time constants vary with process conditions, eg, flow rates and temperatures, and over time. Often such variations do not cause an unacceptable problem. In some instances, however, these variations do cause deterioration in control performance, and the controllers need to be retuned for the different conditions. [Pg.75]

The design of shape-memory devices is quite different from that of conventional alloys. These materials are nonlinear, have properties that are very temperature-dependent, including an elastic modulus that not only increases with increasing temperature, but can change by a large factor over a small temperature span. This difficulty in design has been addressed as a result of the demands made in the design of compHcated smart and adaptive stmctures. Informative references on all aspects of SMAs are available (7—9). [Pg.466]

When the adsorption equihbrium is nonlinear, skewed peaks are obtained, even when N is large. For a constant separation-factor isotherm with R < 1 (favorable), the leading edge of the chromatographic peak is steeper than the trailing edge. Wmen R > 1 (unfavorable), the opposite is true. [Pg.1535]

Displacement Development A complete prediction of displacement chromatography accounting for rate factors requires a numerical solution since the adsorption equilibrium is nonlinear and intrinsically competitive. When the column efficiency is high, however, useful predictious can be obtained with the local equilibrium theoiy (see Fixed Bed Transitions ). [Pg.1536]

The second component is caused by the different harmonic quantities present in the system when the supply voltage is non-linear or the load is nonlinear or both. This adds to the fundamental current, /,- and raises it to Since the active power component remains the same, it reduces the p.f of the system and raises the line losses. The factor /f/Zh is termed the distortion factor. In other words, it defines the purity of the sinusoidal wave shape. [Pg.744]


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See also in sourсe #XX -- [ Pg.397 ]




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