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Government instability

The gas pressure regulators to reduce the supply pressures to the required engine carburetor inlet pressures are usually mounted on the engine. Experience has proved that it is best to supply one regulator per carburetor (on dual-carburetor engines), mounted as close to the carbinetor as possible. This minimizes hne drops and governing instability. [Pg.1001]

The chaotic nature of individual MD trajectories has been well appreciated. A small change in initial conditions (e.g., a fraction of an Angstrom difference in Cartesian coordinates) can lead to exponentially-diverging trajectories in a relatively short time. The larger the initial difference and/or the timestep, the more rapid this Lyapunov instability. Fig. 1 reports observed behavior for the dynamics of a butane molecule. The governing Newtonian model is the following set of two first-order differential equations ... [Pg.228]

In a force-displacement curve, the tip and sample surfaces are brought close to one another, and interact via an attractive potential. This potential is governed by intermolecular and surface forces [18] and contains both attractive and repulsive terms. How well the shape of the measured force-displacement curve reproduces the true potential depends largely on the cantilever spring constant and tip radius. If the spring constant is very low (typical), the tip will experience a mechanical instability when the interaction force gradient (dF/dD) exceeds the... [Pg.195]

This model does not say anything about the mechanism of triple-helix formation, because even in the case of an AON mechanism, nucleation may take place at many positions of the chains and may lead to products the chains of which are staggered. The AON model is based on the assumption that these products are too instable to exist in measurable concentration. As already mentioned, Weidner and Engel142 succeeded in proving by relaxation measurements of al CB2 that the kinetics of in vitro triple-helix formation is governed by more than one relaxation time. This rules out an AON mechanism, but the fitting to the experimentally found equilibrium transition curves nevertheless showed good accommodation and AH° computed from these curves could be confirmed by calorimetric measurement. [Pg.187]

Today it has become clear that the effect of trace elements in living systems, in food, and in the environment depends on the chemical form in which the element enters the system and the final form in which it is present. The form, or species, clearly governs its biochemical and geochemical behaviour. lUPAC (the International Union for Pure and Applied Chemistry) has recently set guidelines for terms related to chemical speciation of trace elements (Templeton et al. 2000). Speciation, or the analytical activity of measuring the chemical species, is a relatively new scientific field. The procedures usually consist of two consecutive steps (i) the separation of the species, and (2) their measurement An evident handicap in speciation analysis is that the concentration of the individual species is far lower than the total elemental concentration so that an enrichment step is indispensable in many cases. Such a proliferation of steps in analytical procedure not only increases the danger of losses due to incomplete recovery, chemical instability of the species and adsorption to laboratory ware, but may also enhance the risk of contamination from reagents and equipment. [Pg.75]

Note that the radial and vertical components are out of phase, and that the coefficient multiplying r is only half that multiplying z. Thus, the effect of the ac field is to exert an oscillatory force on the particle with an effective field strength in the vertical direction that is twice the radial field strength. As a result of the larger field strength in the z-direction, the onset of instability is governed by the z-component of the equation of motion, so we need examine only that component. [Pg.8]

Despite their instability, some unstable atoms may last a long time the half-life of uranium 238, for example, is about 4.5 billion years. Other unstable atoms decay in a few seconds. Radioactive decay is one of the topics of nuclear chemistry, and it involves nuclear forces, as governed by advanced concepts in chemistry and physics, such as quantum mechanics. Researchers do not fully understand why some atoms are stable and others are not, but most radioactive nuclei have an unusually large (or small) number of neutrons, which makes the nucleus unstable. And all heavy nuclei found so far are radioactive—nuclides with an atomic number of 83 or greater decay. [Pg.198]

Since the discovery of lasers it has been known that a derivation of time-dependent equations governing interaction of molecules with electromagnetic cavity modes leads to the so-called spontaneous instabilities. These laser instabilities were also observed experimentally—even for the first laser built by Maiman in 1960. A random, periodic, or quasiperiodic train of spikes in a laser generation is a fundamental instability due to nonlinearity of laser equations. A comprehensive review of this specific laser-related topics was published in 1983 [14]. [Pg.354]

It is important to note two things in this analysis first, the reactions which govern silicate phase equilibria occur in a system closed to large-scale chemical migration. This corresponds to a pore-water sediment system of local equilibrium. Second, the most striking mineralogical change—the crystallization of feldspar—is, in fact, the result of the instability of another phase, montmorillonite. The use of... [Pg.138]

The local stability of a given stationary-state profile can be determined by the same sort of test applied to the solutions for a CSTR. Of course now, when we substitute in a = ass + Aa etc., we have the added complexity that the profile is a function of position, as may be the perturbation. Stability and instability again are distinguished by the decay or growth of these small perturbations, and except for special circumstances the governing reaction-diffusion equation for SAa/dr will be a linear second-order partial differential equation. Thus the time dependence of Aa will be governed by an infinite series of exponential terms ... [Pg.246]


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See also in sourсe #XX -- [ Pg.303 , Pg.304 ]




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Parameters Governing the Rayleigh Instability

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