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Results of Model Calculations

In test examples, we calculated the experimental profile by solving direct diffusion problems (Equation 12.78) with a diffusion coefficient (Equation 12.81) for preset parameters (l)°-a(3) . In order to do so, we used the numerical procedure of solving nonhnear parabolic equations described in [68]. After that, the calculated profile was distorted by the addition of a random concentration proportional to [Pg.418]

The method providing the stability increase for the solution of the inverse diflu-sion problem in a binary system is presented. It is shown that entropy production may serve as a physically adequate regularization term in the discrepancy functional in the process of solving the inverse diffusion problem. Stabilization of the solution [Pg.421]

Model calculations were carried out by the example of a parabohc dependence of the interdiffusion coefficient for a binary system. The efficiency of the method was demonstrated for significant perturbations of the model experimental concentration profile up to 10% with respect to the exact values. The additional smoothing component of the discrepancy functional expressed as squared entropy production can be set to solve any inverse problems of heat and mass transfer. The suggested method, unlike the Matano-Boltzmann method, can be generalized to multicomponent systems with arbitrary sample configurations. [Pg.422]

and Gust, W. (1989) Fundamentals of Grain and Interphase Boundary Diffusion, Ziegler Press, Stuttgart. Larikov, L.N. and Shmatko, O.A. (1976) Cellular Decomposition of Supersaturated Solid Solutions, Naukova Dumka, Kyiv (in Russian). [Pg.422]

Bokstein, B.S., Kopetsky, Ch.V. and Shvindlerman, L.S. (1980) Thermodynamics and Kinetics of Grain Boundaries, Metallurgiya, Moscow (in Russian). Chuistov, K.V. (2003) Aging of Metallic Alloys, Akademperiodika, Kyiv (in Russian). [Pg.422]


IV. RESULTS OF MODEL CALCULATIONS FOR THE LATTICE GAS A. Structure of the Interface... [Pg.169]

Besides we have shown the possibility to apply the results of model calculations to some experimental data and consider a simple approximate approach to the calculation of dimensions of partially cross-linked coils and cross-linking kinetics. The accuracy of this approximation is evaluated bv comparison with Monte Carlo results. [Pg.27]

Figure 12.32 shows the results of model calculations of the effects of the increased aerosols for October 1986 at 43.5°N (Solomon et al., 1996). The calculated change in the odd-oxygen loss rate when the measured aerosol particle surface area is incorporated into the... [Pg.693]

In this paper, the multiphonon relaxation of a local vibrational mode and the non-radiative electronic transitions in molecular systems and in solids are considered using this non-perturbative theory. Results of model calculations are presented. According to the obtained results, the rate of these processes exhibits a critical behavior it sharply increases near specific (critical) value(s) of the interaction. Also the usual increase of the non-radiative transition rate with temperature is reversed at certain value of the non-diagonal interaction and temperature. For a weak interaction, the results coincide with those of the perturbation theory. [Pg.152]

Test laboratories should maintain traceability of their test results in order to claim competence. Traceability of the results can only be demonstrated if all quantities entered into the calculation of the end result are traceable or verified. For measurement results traceability is achieved, as required by the ISO 17025 Standard [1], by calibration of the measuring equipment. If results of model calculations are entered into the calculation of the end result they must be verified as well. Here, verification replaces traceability because results of model calculation are, according to the definition of traceability [2], not traceable. Analogously to the definition of traceability, verification is the process of relating the results of a calculation with a stated reference. Correction factors and their uncertainties, which are extracted by comparing the results of model calculations with the stated reference, take into account the difference between the results and the reference, and establish the evidence for the accuracy of the calculations. [Pg.230]

First, satellite structure on the high binding energy side of, for example, an XPS core-level line (or peak ) corresponds to so-called shake-up (referred to below as s.u. ) and shake-ofF2S-29 effects, the former of which is illustrated, by M+, in Fig. 3.1. Shake-off is just shake-up to the continuum rather than to an unoccupied molecular state. Considerations of (1) are important in comparisons with the results of model calculations while (2) is of use as an indication of the electronic transitions in the molecules under study, an example of which is found in studies of the early stages of interface formation, i.e., the interactions of reactive metal atoms with conjugated polymer surfaces. Since use will be made of these effects in subsequent chapters, they are outlined briefly below. [Pg.39]

Fig. 7.27. The results of model calculations of stage mechanism of Si-O-O-H group formation. Fig. 7.27. The results of model calculations of stage mechanism of Si-O-O-H group formation.
Figure 10.43. Results of model calculations of the carbonate-silicate geochemical cycle illustrated in Figure 10.42. The corresponding changes in atmospheric CO2 and temperature during the last 100 million years are evident. Notice how organic carbon burial may play a strong role as a negative feedback mechanism for a perturbation in atmospheric CO2 driven by tectonics. (After Lasaga et al., 1985.)... Figure 10.43. Results of model calculations of the carbonate-silicate geochemical cycle illustrated in Figure 10.42. The corresponding changes in atmospheric CO2 and temperature during the last 100 million years are evident. Notice how organic carbon burial may play a strong role as a negative feedback mechanism for a perturbation in atmospheric CO2 driven by tectonics. (After Lasaga et al., 1985.)...
Abstract. The synthesis and study of dendrimers has been truly dramatic in the last ten years. This review gives a brief introduction to some of the key concepts and main synthetic strategies in dendrimer chemistry. The focus of the chapter is a survey of modern analytical techniques and physical characterization of dendrimers. Results of model calculations and experiments probing the dimensions and conformation of dendrimers are reviewed. In the final sections the experimental work on dendrimer-polymer hybrids is highlighted. The dense spherical conformation of dendrimers has been combined with the loose random-coil conformation of ordinary polymers to form new hybrids with potentially interesting new properties. [Pg.179]

Fig. 2. Effect of adsorbed water on conductance as a function of doping. The curves marked 0.3 (dashed) and 1.0 ptm (solid) are the results of model calculations for two film thicknesses in which water donates a charge Q to the bulk creating a space-charge layer. [From Fritzsche and Tanielian (1981).]... Fig. 2. Effect of adsorbed water on conductance as a function of doping. The curves marked 0.3 (dashed) and 1.0 ptm (solid) are the results of model calculations for two film thicknesses in which water donates a charge Q to the bulk creating a space-charge layer. [From Fritzsche and Tanielian (1981).]...
In Fig. 20 we portray the results of model calculations for the time dependence of /(f), based on Eqs. (86), (92) and (93), for superfluid ( He)jy clusters with Af = 1.88 X 10 at r = 0.4 K. These calculations were performed for d = 39 A, which falls well in the physically acceptable region of d. This /(f) versus f curve exhibits a near exponential decay with time, with the characteristic lifetime Ttun for electron tunneling. Using the simple relation /(T-ruN)/f(0) = we obtained from Fig. 20 that ttun — 8 x lO s for Ai= 1.88 x 10, which is included in Table VII. [Pg.318]

We have reviewed the literature (3-20) and found that many concurrent and consecutive chemical reactions can occur as a result of the interaction between nitrite and sulfite ions. We will summarize the kinetic results of these reactions and present the results of model calculations that give the concentration profile of species produced in this system as a function of reaction time. The effects of temperature, pH, and concentrations of reactant will be demonstrated. [Pg.129]

Table XV. Results of Model Calculations of the Contribution of Trace Metals from the Water Column and Atmosphere to the Sample Site... Table XV. Results of Model Calculations of the Contribution of Trace Metals from the Water Column and Atmosphere to the Sample Site...
In his interesting article on particle size effects, Bond (27) gives the results of model calculations based on spheres and on cubes with five faces exposed, for Ni, Pt, and Pd. For these simple systems, the fraction of total metal atoms exposed, FE, is related to the diameter or length of a side d (in the figures, d is written with a bar above it to highlight the fact that it is an average value) by the approximate formula... [Pg.72]

Fig. 6-12. Temporal rise of CC13F mixing ratios in (a) the southern and (b) the northern hemispheres according to measurements of Lovelock (1971, 1972, 1974a), Lovelock et al. (1973), Pack et al. (1977), Wilkness et al. (1973, 1975, 1978). Zafonte et al (1975), Hester et al (1975), Heidt et al (1975), Grimsrud and Rasmussen (1975), Singh et al (1977a, 1979b), Krey etal (1977), Cronn et al. (1977), Fraser and Pearman (1978), Tyson et al (1978), Goldan et al. (1980), Leifer et al. (1981), Rasmussen et al (1981, 1982c), and Pierotti et al. (1978). The solid line shows results of model calculations of Logan et al. (1981) based on the release data of Bauer (1979). Ninety percent of the release was assumed to occur in the northern hemisphere. Fig. 6-12. Temporal rise of CC13F mixing ratios in (a) the southern and (b) the northern hemispheres according to measurements of Lovelock (1971, 1972, 1974a), Lovelock et al. (1973), Pack et al. (1977), Wilkness et al. (1973, 1975, 1978). Zafonte et al (1975), Hester et al (1975), Heidt et al (1975), Grimsrud and Rasmussen (1975), Singh et al (1977a, 1979b), Krey etal (1977), Cronn et al. (1977), Fraser and Pearman (1978), Tyson et al (1978), Goldan et al. (1980), Leifer et al. (1981), Rasmussen et al (1981, 1982c), and Pierotti et al. (1978). The solid line shows results of model calculations of Logan et al. (1981) based on the release data of Bauer (1979). Ninety percent of the release was assumed to occur in the northern hemisphere.
The r equations are independent of each other and give only a reasonable result for very dilute surfactant mixtures. Except in this very simple case, no analytical solution exists. In Fig. 4.7. results of model calculations for a solution containing two surfactants are given using a generalized Langmuir isotherm Eq. (2.47). The data were calculated using a finite difference method described in Appendix 4D. [Pg.112]

It must be a goal during the collection of particles in filters that they collide with the medium and adhere upon impact. As shown by the results of model calculations. [Pg.878]

Fig. 12.6 Map representing the mean annual primary production [gCm yr ]. Among other parameters, the distribution of pigment concentration, surface-water temperature and surface irradiance were used for its construction. The representation is the result of model calculations (redrawn after Antoine et al. 1996). Fig. 12.6 Map representing the mean annual primary production [gCm yr ]. Among other parameters, the distribution of pigment concentration, surface-water temperature and surface irradiance were used for its construction. The representation is the result of model calculations (redrawn after Antoine et al. 1996).
Fig. 15. X-ray Faraday effect on Fe in Feo,5Nio,5 [71]. The quantities AjS and A5 are proportional to the Faraday ellipticity ep and the Faraday rotation 0p, respectively. Experimental data (symbols) taken at the L edge of Fe are compared with calculated spectra (full lines). The dashed lines are results of model calculations where the exchange splitting of the 2p core states was neglected. Fig. 15. X-ray Faraday effect on Fe in Feo,5Nio,5 [71]. The quantities AjS and A5 are proportional to the Faraday ellipticity ep and the Faraday rotation 0p, respectively. Experimental data (symbols) taken at the L edge of Fe are compared with calculated spectra (full lines). The dashed lines are results of model calculations where the exchange splitting of the 2p core states was neglected.
Fig. 16. X-ray Voigt effect on Co [72]. Experimental data (circles) taken at the L3 edge of amorphous Co are compared with the calculated Voigt rotation and ellipticities of fee Co (full curves). The dashed lines show results of model calculations where the exchange splitting of the 2p3/2 core state was neglected. Fig. 16. X-ray Voigt effect on Co [72]. Experimental data (circles) taken at the L3 edge of amorphous Co are compared with the calculated Voigt rotation and ellipticities of fee Co (full curves). The dashed lines show results of model calculations where the exchange splitting of the 2p3/2 core state was neglected.
Fig. 24. General outline of the low energy PE bands of the alkyl-tetrathianes 21 and Results of model calculations are indicated beiow ... Fig. 24. General outline of the low energy PE bands of the alkyl-tetrathianes 21 and Results of model calculations are indicated beiow ...
Fig.5.1. Results of model calculation of near-free molecular particle charging ratio of colli si onal flux correction G to free molecular flux Gq vs nondimensionalized Coulomb interaction e parameterizes image potential (see Sect.5.2.2 of text)... Fig.5.1. Results of model calculation of near-free molecular particle charging ratio of colli si onal flux correction G to free molecular flux Gq vs nondimensionalized Coulomb interaction e parameterizes image potential (see Sect.5.2.2 of text)...
In summaiy, the EP flux is a vector in the meridional plane whose components, in quasi-geostrophic theory, measure the zonally averaged northward eddy fluxes of momentum and temperature. Maps of the EP flux and its divergence may be prepared from observations or the results of model calculations. Such maps may be used to infer where and to what extent the eddy motions are acting to change the mean flow and where transient, nonconservative eddy motions are present. [Pg.249]

Comparison with the results of model calculations (Blume et al., 1971) yields the crossover index at the tricritical point (ft 1/2. Just this value is used to describe the properties of polymer systems (section 4.3). [Pg.91]

Fig. 28. Influence of neutron irradiation and annealing on the transition temperature of Y-123 single crystals. The lower panel shows results of model calculations, which relate the above changes predominantly to the formation and removal of additional vacancies in the CuO chains (Sauerzopf et al. 1997, Trushin et al. 1996). Fig. 28. Influence of neutron irradiation and annealing on the transition temperature of Y-123 single crystals. The lower panel shows results of model calculations, which relate the above changes predominantly to the formation and removal of additional vacancies in the CuO chains (Sauerzopf et al. 1997, Trushin et al. 1996).
Long after the onset of a severe accident (more than about 3 weeks), gas-phase iodine is expected to be dominated by organic iodide, with a small contribution from I2 the conclusions drawn from the TMI-2 accident are highly consistent with these results of model calculations. Iodine behavior and distribution, in the long run, are expected to have little relationship to the chemical forms or amounts released into the containment, because the iodine will have had enough time to deposit onto surfaces or in water pools, so that the environmental conditions in the containment will prevail in determining the chemical forms. [Pg.653]


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