Fill coefficient

The packing coefficient p should not be confused with the space-filling coefficient k in molecular crystals, which is calculated on the assumption that atoms contact each other at van der Waals radii, much larger than bond radii (see Sect. 4.3). In fact, in crystals comprising separate molecules, chains or layers (e.g. graphite), each atom participates in two different types of contacts, described by metallic/covalent and van der Waals radii, respectively. In this case the term radius should not be taken literally. Thus, the crystal structures of P, As, Sb and Bi (No = 3) have p = 0.23 but k 0.7. 

Thus K(T) is dimensionless. The adsorption process of a gas on a solid can occur only in a restricted pressure range limited by the saturated vapour pressure of the component i at the same temperature as the adsorption temperature. If the vapour pressure is above ps then adsorption is replaced by liquefaction (Fig. 7.3). The saturation of the adsorbent is established when p is equal to ps. We often use the notion of relative pressure defined by the ratio p/ps. Its value lies between 0 and 1. When the relative pressure is equal to one, the filling coefficient is also equal to one. 

The adsorption and desorption isotherms of water vapor on a series of dealuminated HY zeolites are experimentally drawn to study the change in shape of the isotherm upon both the Si/Al ratio and the dealumination procedure. This study is realized on the one hand, to ascertain whether only the shape of the curve foreshadows the value of the Si/Al ratio and the dealumination procedure and on the other hand, to test the efficiency of the molecular H2O probe for determining the structural and secondary pore volumes. To allow for a satisfactory interpretation the adsorption and desorption isotherm of water vapor on the parent zeolite is studied in wide ranges of temperature and filling coefficient. 

Only a few works deal with the adsorption and desorption equilibrium of water vapor on NaY. The studies are restricted to an isotherm at 25 C in a small range of filling coefficients (ref. 1). 

For the HYgi sample, the isotherm does not reach sufficiently low filling coefficients to characterize the two adsorption domains. On the other hand, the volume in which specific interactions between cation and water predominate is much higher for HYs2 and HYs3 than for NaY and it is located at a value of the relative pressure p/pg much higher too (Table 1). That results from the decrease of the restraint due to dealumination. 

As anticipated, only Wg is obtained for HYs5 since the range of filling coefficients is too narrow at 25°C. Not any micropore volume is characterized for HY(sas6)l nd HY(sas6)2 On the other hand, HYsae is characterized by... 

U, - meaning of linear relaxation coefficient for i - element tomogram s, Vi - volume of object, appropriate i -clement tomogram s, po - meaning of linear relaxation coefficient of a matrix material, (p/p)mei - mass relaxation coefficient of metal, wo - faaor of a pore filling material... 

Here a - surface tension pa - atmospheric pressure 9 - contact angle of crack s wall wetting by penetrant n - coefficient, characterizing residual filling of defect s hollow by a penetrant before developer s application IT and h - porosity and thickness of developer s layer respectively W - minimum width of crack s indication, which can be registered visually or with the use of special optical system. The peculiarity of the case Re < H is that the whole penetrant volume is extracted by a developer. As a result the whole penetrant s volume, which was trapped during the stage of penetrant application, imbibes developer s layer and forms an indication of a defect. 

Mazin I I, Papaconstantopoulos D A and Singh D J 2000 Tight-binding Flamiltonians for Sr-filled ruthenates Application to the gap anisotropy and Flail coefficient in Sr2RuO Phys. Rev. B 61 5223... 

Figure C2.5.8. Plot of the folding times Tp as a fimction of cr nfor tlie 22 sequences. This figure shows tlrat under tire external conditions when tire NBA is tire most populated tlrere is a remarkable correlation between ip and The correlation coefficient is 0.94. It is clear tlrat over a four orders of magnitude of folding times Xp = expf-a, / Oq) where CTq is a constant. The filled and open circles correspond to different contact interactions used in C2.5.1. The open squares are for A = 36.

Static friction decreases with an increase in load, and the static coefficient of friction is lower than the dynamic coefficient. The tendency to creep must be considered carefliUy in FEP products designed for service under continuous stresses. Creep can be minimized by suitable fillers. Fillets are also used to improve wear resistance and stiffness. Compositions such as 30% bronze-fiUed FEP, 20% graphite-filled FEP, and 10% glass-fiber-filled FEP offer high PV values ( 400(kPa-m)/s) and are suitable for beatings. 

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