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Moving phase, definition

The thermodynamic dead volume includes those static fractions of the mobile phase that have the same composition as the moving phase, and thus do not contribute to solute retention by differential interaction in a similar manner to those with the stationary phase. It is seen that, in contrast to the kinetic dead volume, which by definition can contain no static mobile phase, and as a consequence is independent of the solute chromatographed, the thermodynamic dead volume will vary from solute to solute depending on the size of the solute molecule (i.e. is dependent on both ( i )and (n). Moreover, the amount of the stationary phase accessible to the solute will also vary with the size of the molecule (i.e. is dependent on (%)). It follows, that for a given stationary phase, it is not possible to compare the retentive properties of one solute with those of another in thermodynamic terms, unless ( ), (n) and (fc) are known accurately for each solute. This is particularly important if the two solutes differ significantly in molecular volume. The experimental determination of ( ), (n) and( ) would be extremely difficult, if not impossible In practice, as it would be necessary to carry out a separate series of exclusion measurements for each solute which, at best, would be lengthy and tedious. [Pg.32]

For the Berry phase, we shall quote a definition given in [164] ""The phase that can be acquired by a state moving adiabatically (slowly) around a closed path in the parameter space of the system. There is a further, somewhat more general phase, that appears in any cyclic motion, not necessarily slow in the Hilbert space, which is the Aharonov-Anandan phase [10]. Other developments and applications are abundant. An interim summai was published in 1990 [78]. A further, more up-to-date summary, especially on progress in experimental developments, is much needed. (In Section IV we list some publications that report on the experimental determinations of the Berry phase.) Regarding theoretical advances, we note (in a somewhat subjective and selective mode) some clarifications regarding parallel transport, e.g., [165], This paper discusses the projective Hilbert space and its metric (the Fubini-Study metric). The projective Hilbert space arises from the Hilbert space of the electronic manifold by the removal of the overall phase and is therefore a central geometrical concept in any treatment of the component phases, such as this chapter. [Pg.105]

Chromatography is a physical method of separation in which the components to be separated are distributed between two phases, one of which is stationary (the stationary phase), while the other (the mobile phase) moves in a definite direction. A mobile phase is described as a fluid which percolates through or along the stationary bed in a definite direction . It may be a liquid, a gas or a supercritical fluid, while the stationary phase may be a solid, a gel or a liquid. If a liquid, it may be distributed on a solid, which may or may not contribute to the separation process. ... [Pg.24]

Slurry reactors. For three-phase systems the definition of conditions at which (catalyst) particles are in motion is important. Two limiting states with respect to particle behaviour can be distinguished (1) complete suspension, i.e. all particles just move, and (2) uniform suspension, i.e. the particles are evenly distributed over the whole reaction zone. The power required to reach the second state is much higher, while uniform suspension is not often necessary. Circulation of the liquid with the dissolved gas is usually sufficiently fast to provide reactants to the surface of catalyst particles if they are suspended at all. [Pg.354]

Then it resides on the chiral circle with modulus p and phase , , any point on which is equivalent with each other in the chiral limit, mc = 0, and moved to another point by a chiral transformation. We conventionally choose a definite point, (vac p vac) = /,T (Jn the pion decay constant) and (vac Oi vac) = 0, for the vacuum, which is flavor singlet and parity eigenstate. In the following we shall see that the phase degree of freedom is related to spin polarization that is, the phase condensation with a non-vanishing value of Oi leads to FM [20]. [Pg.254]

The quantity kr is so defined that when hr is positive the component A moves to the cold region, and when kr is negative A moves to the hot region. This definition of kr is in agreement with the accepted definitions of previous workers, and in particular with the text books of Chapman and Cowling (C3) and Grew and Ibbs (G12). In the gas phase many authors prefer to write the mass flux in terms of the thermal diffusion factor a, which is defined as... [Pg.176]

Although by definition the system is stable, the phase margin is so close to zero and the gain margin so close to unity that any slight variation in any of the control system parameters or, indeed, in the process conditions, could make the system unstable, i.e. could cause a pole or poles of the system closed-loop transfer function to move into the right half of the complex plane (Section 7.10.1). [Pg.625]

Let us introduce a system of coordinates in which the flame is at rest. For the sake of definiteness we shall make the coordinate plane YOZ coincident with the interface between the condensed phase (briefly, c-phase) and the gas, with the c-phase located to the left at x < 0. In a system in which the flame is at rest, the material must move. The velocity of the material u... [Pg.335]

According to classical theory the vibrational motion of a polyatomic molecule can be represented as a superposition of 3N-6 harmonic modes in each of which the atoms move synchronously (i.e. in phase) with a definite frequency v. These normal modes are characterized by time-dependent normal coordinates which indicate, on a mass-weighted scale, the relative displacement of the atoms from their equilibrium positions (Wilson et al., 1955). Figure 2 shows the general shape of the normal coordinates for a non-linear symmetric molecule AB2. The... [Pg.373]

Once the Project Definition stage is completed and accepted by DTI, the project moves into design and implementation phases. [Pg.68]

Phase space is a 6N- 12 dimensional representation of the atomic (3n - 6) coordinates and their associated (3N- 6) momenta. Reactive trajectories in phase space move from reactant to product. The TS is the hyperplane such that all trajectories that cross this plane do so only once. In other words, trajectories that cross this plane from the reactant side will go on to products without ever turning back and recrossing the plane toward reactant. Given this definition, the rate of reaction is the number of tfajectories that cross the plane per unit time. ... [Pg.513]


See other pages where Moving phase, definition is mentioned: [Pg.17]    [Pg.448]    [Pg.228]    [Pg.4]    [Pg.113]    [Pg.200]    [Pg.361]    [Pg.1173]    [Pg.76]    [Pg.83]    [Pg.634]    [Pg.5]    [Pg.476]    [Pg.2]    [Pg.100]    [Pg.78]    [Pg.355]    [Pg.113]    [Pg.16]    [Pg.700]    [Pg.1]    [Pg.126]    [Pg.433]    [Pg.183]    [Pg.464]    [Pg.11]    [Pg.9]    [Pg.285]    [Pg.329]    [Pg.117]    [Pg.124]    [Pg.90]    [Pg.324]   
See also in sourсe #XX -- [ Pg.29 ]

See also in sourсe #XX -- [ Pg.29 ]




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Moving phase

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