The influence of porosity

Other examples, concerning the water-silica system, are referred to later in the Chapter. [Pg.260]

Type III and Type V isotherms special behaviour of water [Pg.261]

The enhancement of interaction energy in micropores was discussed in some detail in Chapter 4. It was emphasized that the critical pore width d at which the enhancement first appears increases with increasing diameter a of the adsorbate molecule, since the relevant parameter is the ratio d/a rather than d itself. The quantity a is involved because the magnitude of the dispersion interaction increases as the polarizability, and therefore the size, of the molecule increases (cf. p. 5). [Pg.261]

I (curve D). Thus the micropores had been able to enhance the adsorbent-adsorbate interaction sufficiently to replace monolayer-multilayer formation by micropore filling and thereby change the isotherm from being convex to being concave to the pressure axis. [Pg.262]

Physical properties other than magnetic ones are summarized in Table 4, including the influences of porosity and of the measuring direction, ie, parallel ( ) or perpendicular (J ) to the preferred axis. Nearly all properties are clearly anisotropic, the ratio between both values being about 2. For... [Pg.193]

The influence of porosity on the electrochemical activity has not been studied much for electrolyte-supported cells because anode pastes for electrolyte-supported cells are made for screen printing, and thus contain significant amounts of organics, which almost guarantees sufficient porosity. In addition, since the anode thickness for electrolyte-supported cells is only on the order of 50 pm, the concentration polarization itself becomes much less of an issue. In fact, Jiang et al. [44] showed that anode overpotential for cermet anodes prepared with extra graphite pore formers... [Pg.98]

Kusaba A, Fischer 3rd CR, Matulewski TJ, Matsumoto T. Experimental study of the influence of porosity on development of neointima in Gore-Tex grafts a method to increase long-term patency rate. American Surgeon 1981, 47, 347-354. [Pg.81]

Watanabe T. Experimental study on the influence of porosity on the development of the neointima in E-PTFE grafts. Nippon Geka Gakkai Zasshi 1984, 85, 580-591. [Pg.81]

Michelle Leali Costa, Sergio Fraseino M. de Almeida, Mirabel Cerqueira Rezende, The influence of porosity on the interlaminar shear strength of carbon/epoxy and earbon/bismaleimide fabrie laminates. Composites Science and Technology 61 (2001),... [Pg.231]

Earlier investigations presented in the papers [4,14] suggest a higher selectivity of adsorption in respect to preferentially adsorbed component for adsorbents containing narrower mesopores. Similar effect should be expected for microporous materials In order to study the influence of porosity type on adsorption from liquids the measurements of specific surface excess isotherms were performed for binary liquid mixtures benzene + n-heptane / carbon AC-2 and AC-4 benzene + 2-propanol / carbon AC-2 and AC-4. [Pg.351]

Copolymerization of an acryloyl-substituted manganese-salen complex with ethylene glycol dimethacrylate and styrene [32] yielded catalysts that showed low enantioselectivity in the epoxidation of styrene by m-CPBA/NMO or iodosylben-zene (PhIO). The influence of porosity and cross-linking degree on activity was explored and the catalysts could be used repeatedly with no loss of activity for at least three cycles. [Pg.393]

Rossberg, K., G. Raasch, L. Dunsch, and S. Ludwig, The influence of porosity and the nature of the charge storage capacitance on the impedance behaviour of electropolymerized polyaniline films. Journal of Electroanalytical Chemistry, 1998. 443 p. 49... [Pg.146]

Fig. 4 summarizes SPM and SEM data determining the influence of porosity and deposition time on the size and number of grains in the Cu films. [Pg.481]

On the other hand, the influence of porosity on the transport processes cannot be explained simply by the pore volume, but the concept of connectivity or the degree of continuity of the pore system has to be taken into account. At high porosities the interconnected capillary pore system (Figure 1.4) extends from the con-... [Pg.10]

The influence of porosity on the Young s modulus E may be represented by similar empirical formulae, e.g. for hardened cement paste ... [Pg.167]

All the above formulae should be considered as only approximate, because obviously the influence of porosity on the mechanical behaviour of a com-... [Pg.167]

The influence of porosity on the transport processes can be explained by means of the concept of connectivity or the degree of con-... [Pg.947]

Thermal Conductivity The influence of porosity on thermal conductivity 1 [J-s -m -deg ] shall be discussed by using the mathematical model presented in... [Pg.35]

The standard data are determined experimentally on a series of carefully selected reference materials, which give unrestricted monolayer-multilayer adsorption. If the appropriate standard data are selected for the particular gas-solid system, it is therefore possible to identify the influence of porosity (micropore filling or capillary condensation) on the path of the isotherm. In this manner it is possible to check the validity of the BET-area and in favourable cases to evaluate the total surface area, the internal area and the external area ... [Pg.20]

Very few attempts have been made to investigate the influence of porosity on the course of adsorption from solution. Recent work in this laboratory has shown that in favourable cases it is possible to extend the application of the OCg-method for the analysis of solute isotherms. The analysis gave a clear indication of the effect of primary micropore filling in distorting the isotherm shape when applied to certain L-type isotherms (e.g. of iodine and salicylic acid adsorption by activated charcoals), but difficulties were encountered when the non-porous reference material gave H-shaped or S-shaped isotherms (i.e. either very high or very low affinity). [Pg.24]

The Influence of Porosity and Permeability on Corrosion Resistance of Refractories... [Pg.187]

Figure 12.33 The influence of porosity on the modulus of elasticity for aluminum oxide at room temperature. The curve drawn is according to Equation 12.9.

Figure 6.36 illustrates the influence of porosity change across the package layers on dye transfer behaviour. Dotted and dashed curves represent the CDEP when the package porosity linearly decreases from 0.5 to 0.462, and increases from 0.5 to 0.538 (or the package density increases and decreases) with distance... [Pg.146]

The third factor contains the influence of porosity and model- (or grain-) shape G. [Pg.246]

This model helps, for example, to estimate the influence of porosity (oj = 0,... [Pg.453]

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