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Conservation condition

The treatment of such order-disorder phenomena was initiated by Gorsky (1928) and generalized by Bragg and Williams (1934) [5], For simplicity we restrict the discussion to the synnnetrical situation where there are equal amounts of each component (x = 1/2). The lattice is divided into two superlattices a and p, like those in the figure, and a degree of order s is defined such that the mole fraction of component B on superlattice p is (1 +. s)/4 while that on superlattice a is (1 -. s)/4. Conservation conditions then yield the mole fraction of A on the two superlattices... [Pg.632]

If we allow for exchange with the gas phase, then h x) does not obey a conservation condition and we have the simple Ginzburg-Landau equation ... [Pg.861]

This delta function can be used in the expression for R-p to constrain the multidimensional integral over vibration-rotetion coordinates (denoted Q) to those specific values which obey the energy conservation condition... [Pg.299]

It will now be shown that the current density is uniquely determined from the magnetic field density. From the Fourier transform of the current conservation condition (15) we have... [Pg.259]

The analytical techniques proposed in the literature generally give reliable information on lipids present in the paint layer. However, the presence of lipid mixtures and of particular environmental conservation conditions may affect the lipid pattern to such an extent that their identification may be very difficult and sometimes erroneous. Thus, a multianalytical approach is recommended which integrates chromatographic data with techniques such as mapping based on Fourier transform infrared spectroscopy or SIM on cross-sections, in order to better understand the distribution of lipids in the various paint layers. [Pg.209]

We can also express this conservation condition in terms of the fractional p character of bonding ( >(AH)) and sigma nonbonding (/p(A )) hybrids,... [Pg.135]

We now have to make the definition of x more explicit and decide where to locate the origin (the Matano interface) for the conservation condition above to hold. In the laboratory, one would use an arbitrary coordinate X, such as the distance to one end of the experimental device, then... [Pg.425]

The kinetic energy of the ejected electrons Ekin(e) is measured and the ionization energy or ionization potential IP is obtained from the energy conservation condition. [Pg.160]

Combining Eq. (6.8) and the conservation condition, the following expression for the relative percentage of release is derived ... [Pg.192]

In order to determine the averaged occupation numbers n,. for the considered atoms (3 < Z 30), we have solved numerically the system of highly non-linear equations composed from the particle number conservation condition (17) and the plateau condition (24). It was found that the condition (25) is fulfilled with desired accuracy (with less than 1% discrepancy for 5iEhfr) for values of M > 35, and the roots Yo and X found at M = 35 allow a correct determination of the n. ... [Pg.63]

In (14), N(E) is the density of state function, i.e. the number of eigenstates of the electron (in the given energy scheme) between E tmd E + dE. Equation (14) is then just a conservation condition for the number of electrons N. [Pg.29]

There is a condition of momentum conservation for photons and electrons which must also be satisfied in the photoemission process. For band electrons, for which the Bloch wavefunctions are characterized by the wavenumber k (proportional to the momentum p of the electron), the momentum conservation condition is important to determine the angular distribution of the photoemitted electrons. Angular J esolved FhotoEmission spectroscopy (ARPES), schematized in Fig. 2, is potentially able to provide, and has been used to obtain, the E(fc) dispersion curves for solids. [Pg.202]

In this case, the whole process is determined by the change of the wavefunction t>in of the photoemitted j electron, and the energy conservation condition (4) can... [Pg.202]

The principal selection rule is provided as in optical transitions, by the momentum conservation condition ... [Pg.210]

Imposing the particle conservation condition, which introduces a new Fermi level A, we can define the so-called generalized occupation numbers... [Pg.166]

Let us denote with E rii ) the stationary value of the functional (32) with respect to arbitrary occupation numbers rii = (ni,rz2,...) = n for the orbitals 4>i, satisfying the particle conservation condition, i.e. ... [Pg.168]

Fig. 5.10 State of lead coins after different conservation conditions (a) coin protected by a passive surface (b) coin with corrosion localized on protruding features (c) coin nearly disintegrated due to corrosive attack (courtesy Societe Archeologique de Namur, from [267])... Fig. 5.10 State of lead coins after different conservation conditions (a) coin protected by a passive surface (b) coin with corrosion localized on protruding features (c) coin nearly disintegrated due to corrosive attack (courtesy Societe Archeologique de Namur, from [267])...
In the last 25 years, calculations of the detonation properties of condensed explosives from their chemical compositions and densities have been approached in various ways.2 All have used the necessary conservation conditions for steady flow with the detonation discontinuity satisfying the Chapman-Jouguet hypothesis (minimum detonation velocity compatible with the conservation conditions or sonic flow behind the discontinuity in a reference frame where the discontinuity is at rest). In order to describe the product state and the thermodynamic variables which fix its composition, an equation of state applicable to a very dense state is required. To apply this equation to a mixture of gaseous and solid products, a mixing rule is also needed and the temperature must be explicitly defined. Of the equations of state for high-density molecular states which have been proposed, only three or four have been adapted to the calculation of equilibrium-product compositions as well as detonation parameters. These are briefly reviewed in order to introduce the equation used for the ruby computer code and show its relation to the others. [Pg.1]

Returning to the general case in which kb is permitted to be nonzero, we comment on one more feature of this stochastic model, namely that the equilibrium distribution, considered as a function of kfjkb, displays a first order transition in the limit K = oo. With dNi(oo)/dt = 0 the equilibrium solution to Eqs. (1)—(3) is seen to be of the form Af(oo) = A(kfjkby. The conservation condition, Eq. (6), gives the value of A, and we have... [Pg.190]

Chemical diffusion has been treated phenomenologically in this section. Later, we shall discuss how chemical diffusion coefficients are related to the atomic mobilities of crystal components. However, by introducing the crystal lattice, we already abandon the strict thermodynamic basis of a formal treatment. This can be seen as follows. In the interdiffusion zone of a binary (A, B) crystal having a single sublattice, chemical diffusion proceeds via vacancies, V. The local site conservation condition requires that /a+/b+7v = 0- From the definition of the fluxes in the lattice (L), we have... [Pg.75]

Suppose that the system is at equilibrium with all three species at their equilibrium chemical potentials. We then make small changes in their numbers subject to the conservation condition... [Pg.40]

Finally, verify that this solution satisfies the conservation condition... [Pg.119]

From the mass conservation condition, it is obtained that... [Pg.595]

If the retardation factor approach is adopted for performance assessment, the distribution coefficient should be measured under conditions that represent a worst case competition scenario. One approach to approximating conservative conditions is to pre-wash the zeolite in an effort to saturate the exchange sites with calcium, the chief competitor (e g., Cantrell, 1996). Alternatively, it may suffice to operate the columns until full breakthrough of the competing solutes is observed, as suggested by Figure 4, followed by the analysis of spatial concentrations. [Pg.131]

According to their spokesman, the Max-Planck-Corporation has no proof that the samples are really from Auschwitz. Even if they are from there, according to expert opinion, it is certainly no wonder that no traces of hydrogen cyanide were found, because cyanide compounds disintegrate quickly. In earth this takes six to eight weeks and in stone they can only be preserved by absolute conservation conditions, including complete exclusion of air and bacteria . [Pg.385]

In the dpa notice it was stated that cyanide compounds will last in stone only under absolute conservation conditions , but in contrast to that, in the masonry of the cases of interest here and investigated in detail in this report, the disinfestation chambers of Auschwitz, hydrogen cyanide formed extremely long-lasting iron cyanide compounds of the Iron Blue type. See the arguments given above for proof of this. [Pg.387]

For a point source, z is zero, and from equ. (10.6b) it follows that tp = const. This means that the electrons ejected from the source move in a plane which contains the z-axis. Hence, the focal point must also be in this plane, and this fact considerably facilitates the discussion of the optical properties of the spectrometer. Due to the conservation conditions, one is left with only one differential equation which describes the radial movement of the electron, i.e.,... [Pg.379]

The calculation of the equilibrium composition of a system of chemical reactions with equcalcc is based on minimizing the Gibbs energy subject to the conservation condition An = nc. This is accomplished by using a Lagrangian L defined by... [Pg.109]


See other pages where Conservation condition is mentioned: [Pg.752]    [Pg.2007]    [Pg.2053]    [Pg.57]    [Pg.8]    [Pg.11]    [Pg.205]    [Pg.160]    [Pg.424]    [Pg.27]    [Pg.318]    [Pg.382]    [Pg.51]    [Pg.360]    [Pg.24]    [Pg.85]    [Pg.30]    [Pg.202]    [Pg.394]    [Pg.308]    [Pg.20]    [Pg.25]    [Pg.273]   
See also in sourсe #XX -- [ Pg.232 ]

See also in sourсe #XX -- [ Pg.279 ]




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