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Friedel-Anderson

Flory polymerization kinetics (4). Henrici-Olive and Olivd (5) proposed the use of the related equation of Schulz (6). Over the last decade the Flory equation has been used frequently to describe product distributions in FT synthesis. The Friedel-Anderson (i) or Flory (4) approaches apply when the rates of propagation and termination are independent of carbon number. We do not attempt here to discuss all previous research on FT product distributions except to say that the literature contains many examples of product distributions that obey Flory kinetics within relative narrow carbon number ranges and many that do not. [Pg.384]

Indeed, an earlier investigation of the ThCe system revealed that the depression of TJT with n followed a modified exponential relation of the form T o/Tcd = exp[-An/(l-Dn)], while the depression of ACIACo with TJTc conformed to the linear BCS law of corresponding states (Huber and Maple, 1970). The modified exponential relation for TJT vs n was derived theoretically by Kaiser (1970) for matrix-impurity systems in which the impurities contribute localized d or f states which are nonmagnetic in the sense of the Friedel-Anderson model (i.e., ttAIU > 1) A and D can be related to the Friedel-Anderson parameters Ni Ep) and U which characterize the localized d or f state. On the basis of thermoelectric power measurements. Cooper and Rizzuto (1973) have suggested that the characteristic spin fluctuation temperature of the ThCe system is of the order of 10 K. Measurements of the lattice constant as a function of relative Th-Ce composition indicate that the valence of Ce is 3.25 in the ThCe system up to 20at.% Ce (Harris and Raynor, 1%4). [Pg.811]

In Fig. 6, it is seen that the americium metallic volume at T = 0, p = 0, is well reproduced by spin-polarized band calculations. The same band-calculations predict the pressure p in which the transition from localized to itinerant behaviour occurs for americium. Here, we want to present the simplified Friedel-type model (Skriver, Anderson and Johansson ) by which the spin-polarized americium system is described and both transitions, i and ii, predicted. One word of caution the model, as well as the band calculations, do not account for the change in structure accompanying the transition, and which is an important fact in actinide metals, which will be discussed in the following... [Pg.103]

Selectivity in the Fischer-Tropsch (FT) synthesis is directly related to carbon number distributions. These distributions were first discussed by Friedel and Anderson (i), who used an approach suggested by Herrington (2) to relate the rates of formation of hydrocarbon chains to the rates of chain termination. Later, it was shown (5) that the approach in Ref. (i) was similar to that used in... [Pg.383]

Concurrent with FTS mechanism studies, product distribution models were developed based on the analysis of product composition. Friedel and Anderson28 29 in the 1950s published the Anderson-Schulz-Flory (ASF) distribution model to predict the wide range of products yielded from FTS. The equation is shown as follows ... [Pg.503]

Friedel, R.A. and Anderson, R.B. Composition of synthetic liquid fuels. I. Product distribution and analysis of C5-C8 paraffin isomers from cobalt catalyst. Journal of American Chemical Society, 1950, 72, 1212. [Pg.521]

Anderson, K. W. and Tepe, J. J. 2002. The first intermolecular Friedel-Crafts acylation with P-lactams. Org. Lett. 4 459M61. [Pg.29]

Anderson, Krieg, and Friedel (81) Differential reaction rate studies on Fischer-Tropsch catalysts. [Pg.317]

When SE is higher than ca. KT, the distribution of states at the Fermi level cannot be considered any more as a quasi continuum and there will be a transition from the metallic to the molecular state of the aggregate. A rou calculation has been made by Friedel [S] assuming that the band width is equal to about 10 eV. At room temperature 5E—KT for 10 , 30 and 10 atoms for linear ape, film and spherical shape of the particles respectively. Using the same kind of rough calculation, Anderson [121] finds a deviation from the metallic state for particleshaving less than about 500 atoms. [Pg.174]

From what we introduced above, for the industrial reactor, the method should consist of gas phase and the slurry phase (Baten and Krishna, 2003 Krishna et al., 1999, 2000, 2001 Troshko and Zdravistch, 2009), gas-liquid phase and particle phase (Eidus, 1967 Friedel and Anderson, 1950), meanwhile, the gas phase was treated as single bubble, double bubble, and multibubble phase (equihbrium state). The model considers two phase of gas and slurry as shown in Eqs. (26) and (27) ... [Pg.359]


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Friedel-Anderson model

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