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Phase creation

Figure 2 General separation techniques (a) separation by phase creation (b) separation by phase addition (MSA mass separating agent) (c) separation by barrier (d) separation by solid agent (e) separation by force field or gradient... Figure 2 General separation techniques (a) separation by phase creation (b) separation by phase addition (MSA mass separating agent) (c) separation by barrier (d) separation by solid agent (e) separation by force field or gradient...
Table 1 Common separation operations based on phase creation or addition (MSA mass-separating agent ESA energy-separating agent)... Table 1 Common separation operations based on phase creation or addition (MSA mass-separating agent ESA energy-separating agent)...
The coexisting liquid and vapor streams associated with phase separation may be brought about by phase creation or by phase addition. Phase creation is accomplished by heat transfer to and from the column as in distillation, where heat is added in the reboiler to vaporize some of the liquid, and heat is removed in the condenser to condense some of the vapor. Phase addition is accomplished by sending an auxiliary stream to the column a liquid absorbent to an absorber or a stripping vapor stream to a stripper. [Pg.137]

Creation and annihilation of phase quanta in FD Hilbert space can be defined in a close analogy to the creation and annihilation of photons, as given by Eq. (8). Phase annihilation, < )v, and phase creation, <[>]., operators can be introduced with the help of the relation <1>V = (j)]4>s. for the Pegg-Barnett phase operator, given by (7). The FD phase annihilation and creation operators in the phase-state basis, have the following form [16]... [Pg.160]

There are two physical phenomena which are the sources of leakage current changes (i) field crystallization - irreversible process of crystalline phase creation and (ii) the second physical process which is partially reversible. We suppose that the ions diffusion is the source of this reversible process. There are residual atoms as interstitials in the insulating layer and they can diffuse in high electric field and at elevated temperature. Then potential barrier between the cathode and anode is changed due to the electric charge redistribution. Then fitting equation (1) with the square root of time is acceptable from the physical point of view. [Pg.1824]

As pointed out previously, the separation of homogeneous fluid mixtures requires the creation or addition of another phase. The most common method is by repeated vaporization and condensation— distillation. The three principal advantages of distillation are... [Pg.74]

The appropriate quantum mechanical operator fomi of the phase has been the subject of numerous efforts. At present, one can only speak of the best approximate operator, and this also is the subject of debate. A personal historical account by Nieto of various operator definitions for the phase (and of its probability distribution) is in [27] and in companion articles, for example, [130-132] and others, that have appeared in Volume 48 of Physica Scripta T (1993), which is devoted to this subject. (For an introduction to the unitarity requirements placed on a phase operator, one can refer to [133]). In 1927, Dirac proposed a quantum mechanical operator tf), defined in terms of the creation and destruction operators [134], but London [135] showed that this is not Hermitean. (A further source is [136].) Another candidate, e is not unitary. [Pg.103]

There are two mechanisms by which a phase change on the ground-state surface can take place. One, the orbital overlap mechanism, was extensively discussed by both MO [55] and VB [47] formulations, and involves the creation of a negative overlap between two adjacent atomic orbitals during the reaction (or an odd number of negative overlaps). This case was temied a phase dislocation by other workers [43,45,46]. A reaction in which this happens is... [Pg.344]

An additional effect of the use of an organic medium in the catalyst preparation is creation of mote defects in the crystalline lattice when compared to a catalyst made by the aqueous route (123). These defects persist in the active phase and are thought to result in creation of strong Lewis acid sites on the surface of the catalysts (123,127). These sites ate viewed as being responsible for the activation of butane on the catalyst surface by means of abstraction of a hydrogen atom. [Pg.454]

A spray comprises a cloud of liquid droplets randomly dispersed ia a gas phase. Depending on the appHcation, sprays may be produced ia many different ways. The purposes of most sprays are (/) creation of a spectmm of droplet sizes to iacrease the Hquid surface-to-volume ratio, (2) metering or control of the hquid throughput, (J) dispersion of the Hquid ia a certain pattern, or (4) generation of droplet velocity and momentum. [Pg.327]

Separation operations achieve their objective by the creation of two or more coexisting zones which differ in temperature, pressure, composition, and/or phase state. Each molecular species in the mixture to be separated reacts in a unique way to differing environments offered by these zones. Consequently, as the system moves toward equilibrium, each species establishes a different concentration in each zone, and this results in a separation between the species. [Pg.1242]

The acceptable separation of Am(III) and Cm(III) by countercurrent chromatography (CCC) was achieved using both isocratic elution, and a new approach to the creation of the reagent concentration gradient in the stationary phase [1]. This way allows reduce the experiment length. [Pg.282]

Uncontrolled con-densation/absorp-tion of vapor phase component resulting in vacuum creation inside vessel. [Pg.48]

The mechanism of ion polymerization in formaldehyde crystals proposed by Basilevskii et al. [1982] rests on Semenov s [1960] assumption that solid-phase chain reactions are possible when the arrangement of the reactants in the crystal prepares the configuration of the future chain. The monomer crystals capable of low-temperature polymerization fulfill this condition. In the initial equilibrium state the monomer molecules are located in the lattice sites and the creation of a chemical bond requires surmounting a high barrier. However, upon creation of the primary dimer cation, the active center shifts to the intersite, and the barrier for the addition of the next link... [Pg.129]

This function is intermediate between the parallel model and the series model and referred to as the logarithmic law of mixture shown in curve 3. The law of mixture is valid for a composite system when there is no interaction in the interface. However, it is natural to consider that interaction will occur in the interface due to contact between A and B. Then considering the creation of interfacial phase C, different from A and B, the following equation can be presented ... [Pg.816]

Although there is no limit theoretically to the shapes that can be created, practical considerations must be met. These relate not only to product design but also to mold or die design, since these must be considered one entity in the total creation of a usable, economically feasible product. In the sections that follow, various phases considered important in the creation of such products are examined for their contribution to and effect on design and function. [Pg.156]


See other pages where Phase creation is mentioned: [Pg.143]    [Pg.2917]    [Pg.177]    [Pg.189]    [Pg.143]    [Pg.2917]    [Pg.177]    [Pg.189]    [Pg.67]    [Pg.680]    [Pg.2572]    [Pg.2596]    [Pg.3057]    [Pg.178]    [Pg.252]    [Pg.430]    [Pg.132]    [Pg.505]    [Pg.254]    [Pg.1418]    [Pg.263]    [Pg.163]    [Pg.182]    [Pg.83]    [Pg.470]    [Pg.380]    [Pg.384]    [Pg.522]    [Pg.512]    [Pg.12]    [Pg.18]    [Pg.892]    [Pg.270]    [Pg.392]    [Pg.387]    [Pg.136]   


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