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Value appropriation

Conversely, if the pressure of O2 above a crystalline oxide is decreased below the equilibrium value appropriate for the stoichiometric composition, oxygen boils out of the lattice leaving supernumerary metal atoms or lower-valent ions in interstitial positions, e.g. ... [Pg.642]

Vibrational wavefunctions for the states u = 0 and u = 1 are shown in Figures 1.4 and 1.5. For the sake of illustration, I have taken numerical values appropriate to The x-axis legend variable is Note that the... [Pg.30]

Value appropriate to a solution containing 0.29 M perchloric acid. b Measured for a solution in benzene, a correction being applied for benzene mercuration. c Estimated rate for competitive mercuration with benzene. [Pg.192]

As the temperature of an N2/O2 mixture is increased above 2000 K the observed concentration of NO (as well as those for NO2, N, O, and other species) will approach the equilibrium values appropriate for that temperature. As the temperature of the mixture of these gases decreases, the concentrations will follow the equilibrium values. Equilibrium will be maintained as long as the time scale for the chemical reaction is shorter than the time scale for the temperature change (that is, the chemical reaction is more rapid than the temperature change). The time scale for the chemical reaction increases rapidly as tpe temperature decreases because of the large activation energies. The concentrations of NO at ambient conditions reflect the lowest temperature at which the system was in equilibrium as it cooled. [Pg.102]

Here, m is the number of electrons involved in the change, Rq the initial bond distance, and N the number of ligand atoms bonded to the metal. Covalent as well as electrostatic theories suggest that n 5. Note that for both A and /, the values appropriate for the initial state of bond length Rq should be employed. [Pg.84]

With the addition of a pseudopotential interaction between electrons and metal ions, the density-functional approach has been used82 to calculate the effect of the solvent of the electrolyte phase on the potential difference across the surface of a liquid metal. The solvent is modeled as a repulsive barrier or as a region of dielectric constant greater than unity or both. Assuming no specific adsorption, the metal is supposed to be in contact with a monolayer of water, modeled as a region of 3-A thickness (diameter of a water molecule) in which the dielectric constant is 6 (high-frequency value, appropriate for nonorientable dipoles). Beyond this monolayer, the dielectric constant is assumed to take on the bulk liquid value of 78, although the calculations showed that the dielectric constant outside of the monolayer had only a small effect on the electronic profile. [Pg.60]

In this survey the nephelauxetic ratios have been calculated for the neutral metallocenes using the free-ion B values appropriate for the corresponding M( ) oxidation state, and for the metallicenium species the free-ion B values are similarly those for the Af(III) oxidation state. In both cases the B values calculated by the J rgensen-Racah relationship, and listed by Allen and Warren (60) have been used. [Pg.74]

The values and Tgf determined from the fitting to T j (2wi) from the red and yellow solutions along with estimates for the blue solution are shown in Table I. The results for fgj determined from linear absorption data and f f determined from the Yj data for all three solutions are also included in Table I. Note that these oscillator strengths correspond to the values appropriate for polarization parallel to the chain direction. Though the restricted data for the blue solution yields significant uncertainties in the and Tgf values, f f for the blue solution is reasonably well determined nevertheless. [Pg.206]

The results from OILEQUIL can be converted to an active layer thickness in several ways. First, the total thickness of the zone shown to contain product could be used. This would overestimate the thickness of the recoverable product layer, because oil at low saturations is immobile. Second, one could follow Van Dam (1967) in assuming a residual oil saturation of 20% (or another value appropriate to the soil and LNAPL involved) and pick out the thickness of the zone with greater than 20% product saturation from the OILEQUIL tabular output. In equation form,... [Pg.185]

When the scan of the potential reaches a value appropriate for the reduction of Ox, the concentration of Ox at the electrode surface begins to decrease with respect to that present in the bulk of the solution, Cqx. This implies that a concentration gradient (8C0x(x,t)/8x) becomes established (recalling that 8CQx(x,r) = C0x(x,t)-C 0x), and thus, from... [Pg.51]

We now assume that we have properly recorded rocking curves available, and that a substrate with a single epitaxial layer >0.5 //m thick (and less than, say, 5 m) is measured. This will result in two peaks, one each from the substrate and layer. The same analysis will apply to multiple peaks (other than those from superlattices) provided that they are well separated so that interference effects are minimised. The basic parameters are derived as follows, with the symmetric reflection used unless otherwise specified. The examples are given for (001) substrates and layers, but are quite general (with the caution that if the Poisson ratio is required, the value appropriate to the crystal orientation should strictly be used). [Pg.56]

Electrodeposition of composition-modulated films was first performed by Brenner in 1939 (1) by employing two separate baths for the two components and a periodic immersion of the deposit in the two baths. This is too cumbersome a method to be adopted in practice. Deposition from a single bath with the presence of salts of the two components of the multilayer is what is desired, but there was a serious problem with the deposition of two metals from one bath. Specifically, whereas a layer of the more noble member can be deposited by choosing the potential to be between the reduction potentials of the two metals, one can expect that when the potential is set to a value appropriate for reduction of the less noble member, both will be deposited, resulting in an alloy layer rather than a pure metal. Thus, to nobody s surprise, even as recently as 1983, Cohen et al. (2), were able to deposit only a layered structure of alloys rather than pure metals. In addition they cast doubt on the possibility that a modulation cycle (the thickness of the basic layers, the periodic repetition of which... [Pg.290]

The heats of formation of alkenes may sometimes be obtained by combining heats of hydrogenation with the heat of formation of the saturated product. This procedure has been used to obtain heats of formation of many strained alkenes. The heats of hydrogenation are usually measured in solution, and may differ somewhat from the value appropriate for the gas phase. Thus, the heats of formation of alkenes obtained in this way have a somewhat higher uncertainty than those obtained from heats of combustion. [Pg.719]

Differences leading to the lower values of P cited in the earlier LASL and later Russian reports, and by Petrone, as contrasted with the higher values in the later LASL and earlier Russian reports, appear to be rooted in the thick-plate vs thin-plate question.21 If Petr one s and current Russian interpretations are correct, and if in addition some of the NOL measurements do, in fact, represent lower than infinite diameter values, appropriate adjustments would lead to much better over-all agreement of the experimental results with Eq. (1) than is recorded in the present paper. If, on the other hand, the current LASL interpretations are the more valid, the general form of Eq. (1) would still seem to be appropriate, but an upward adjustment of K, probably by about 6%, might be indicated. [Pg.27]

The final E° value is the sum of the individual values appropriately weighted by their respective numbers of electrons, the sum then being divided by the total number of electrons transferred in the final equation. This is because the electrons do not cancel out in such cases. [Pg.76]


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See also in sourсe #XX -- [ Pg.3 , Pg.4 , Pg.154 ]




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