Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Break-down point

In emergency situations with depressurization of the primary circuit pressure system of such a scale as DN 600 and higher, it is required to determine the pump characteristics taking into account possible cavitation. For the pumps of the primary circuit at 152 000 Pa nominal value of absolute argon pressure in the gas reactor cushion, the flow rate value at the break-down point is 15 800 m /hr. [Pg.135]

The case when one of the differential closed paths surrounds the point B[a,b) (see Fig. 17fi). Flere the derivation breaks down at the transition from Eqs. (C.5)-(C.7) and later, from Eqs. (C.7)-(C.8), because Xp and x, become infinitely large in the close vicinity of and therefore their... [Pg.725]

The total electron density contributed by all the electrons in any molecule is a property that can be visualized and it is possible to imagine an experiment in which it could be observed. It is when we try to break down this electron density into a contribution from each electron that problems arise. The methods employing hybrid orbitals or equivalent orbitals are useful in certain circumsfances such as in rationalizing properties of a localized part of fhe molecule. Flowever, fhe promotion of an electron from one orbifal fo anofher, in an electronic transition, or the complete removal of it, in an ionization process, both obey symmetry selection mles. For this reason the orbitals used to describe the difference befween eifher fwo electronic states of the molecule or an electronic state of the molecule and an electronic state of the positive ion must be MOs which belong to symmetry species of the point group to which the molecule belongs. Such orbitals are called symmetry orbitals and are the only type we shall consider here. [Pg.261]

Cardiomyopathy. Cardiomyopathy, or diseased heart muscle, may reach a point at which the heart can no longer function. It arises from a combination of factors, including hypertension, arrhythmias, and valve disease. Other problems, such as congestive heart failure, cause the interrelated heart—lung system to break down. Because the heart can no longer adequately pump, duid builds up in the lungs and other areas. [Pg.180]

Phenomena at Liquid Interfaces. The area of contact between two phases is called the interface three phases can have only aline of contact, and only a point of mutual contact is possible between four or more phases. Combinations of phases encountered in surfactant systems are L—G, L—L—G, L—S—G, L—S—S—G, L—L, L—L—L, L—S—S, L—L—S—S—G, L—S, L—L—S, and L—L—S—G, where G = gas, L = liquid, and S = solid. An example of an L—L—S—G system is an aqueous surfactant solution containing an emulsified oil, suspended soHd, and entrained air (see Emulsions Foams). This embodies several conditions common to practical surfactant systems. First, because the surface area of a phase iacreases as particle size decreases, the emulsion, suspension, and entrained gas each have large areas of contact with the surfactant solution. Next, because iaterfaces can only exist between two phases, analysis of phenomena ia the L—L—S—G system breaks down iato a series of analyses, ie, surfactant solution to the emulsion, soHd, and gas. It is also apparent that the surfactant must be stabilizing the system by preventing contact between the emulsified oil and dispersed soHd. FiaaHy, the dispersed phases are ia equiUbrium with each other through their common equiUbrium with the surfactant solution. [Pg.234]

In either equation, /c is given by Eq. (16-84) for parallel pore and surface diffusion or by Eq. (16-85) for a bidispersed particle. For nearly linear isotherms (0.7 < R < 1.5), the same linear addition of resistance can be used as a good approximation to predict the adsorption behavior of packed beds, since solutions for all mechanisms are nearly identical. With a highly favorable isotherm (R 0), however, the rate at each point is controlled by the resistance that is locally greater, and the principle of additivity of resistances breaks down. For approximate calculations with intermediate values of R, an overall transport parameter for use with the LDF approximation can be calculated from the following relationship for sohd diffusion and film resistance in series... [Pg.1516]

From 160°C to room temperature. The lead-rich phase becomes unstable when the phase boundary at 160°C is crossed. It breaks down into two solid phases, with compositions given by the ends of the tie line through point 4. On further cooling the composition of the two solid phases changes as shown by the arrows each dissolves less of the other. A phase reaction takes place. The proportion of each phase is given by the lever rule. The compositions of each are read directly from the diagram (the ends of the tie lines). [Pg.349]

One further breaks down the secondary electron contributions into three groups SEI, SEII and SEIII. SEIs result from the interaction of the incident beam with the sample at the point of entry. SEIIs are produced by BSE s on exiting the sample. SEIIIs are produced by BSEs which have exited the surface of the sample and further interact with components on the interior of the SEM usually not related to the sample. SEIIs and SEIIIs come from regions far outside that defined by the incident probe and can cause serious degradation of the resolution of the image. [Pg.72]

The formulation above allows a more general equation of state for the combustion products (Kuhl 1983). The method described breaks down for low piston velocities, where the leading shock Mach number approaches unity. In such cases, the numerical integration marches into the point (F = 0, Z = 1), which is a singularity. [Pg.100]

It is clear that the one-to-one correspondence assumption readily breaks down, notoriously at the position halfway along the path, the saddle point position. This is considered as the most important point apart from the initial position [20, 21], because conventionally the force has been calculated by averaging its values at initial position and saddle point. Until now only the model-pseudopotential method was used, which... [Pg.470]

Often, a reasonable and convenient way to understand the heat transfer process in a heat exchanger unit is to break down the types of heat transfer that must occur such as, vapor subcooling to dew point, condensation, and liquid subcooling. Each of these demands heat transfer of a different type, using different AT values, film coefficients, and fouling factors. This is illustrated in Figure 10-36. It is possible to properly determine a weighted overall temperature... [Pg.58]

Note that the break at Point A on Figure 10-67B at Re = 2,100 indicates where the film is believed to become turbulent. McAdams discusses the two regions on the figure, streamlined at the top and turbulent on the way down, with a transition region in between ... [Pg.116]

Pitting of nickel and nickel alloys, as of other metals and alloys, occurs when passivity breaks down at local points on the surface exposed to the corrosive environment, at which points anodic dissolution then proceeds whilst the... [Pg.775]


See other pages where Break-down point is mentioned: [Pg.248]    [Pg.248]    [Pg.272]    [Pg.562]    [Pg.559]    [Pg.707]    [Pg.297]    [Pg.149]    [Pg.159]    [Pg.273]    [Pg.87]    [Pg.267]    [Pg.269]    [Pg.122]    [Pg.508]    [Pg.188]    [Pg.501]    [Pg.502]    [Pg.30]    [Pg.598]    [Pg.228]    [Pg.153]    [Pg.399]    [Pg.39]    [Pg.341]    [Pg.117]    [Pg.581]    [Pg.56]    [Pg.132]    [Pg.285]    [Pg.322]    [Pg.467]    [Pg.112]    [Pg.802]    [Pg.1306]    [Pg.25]    [Pg.245]    [Pg.227]   
See also in sourсe #XX -- [ Pg.59 ]




SEARCH



Break point

Breaking down

© 2024 chempedia.info