Mutual intersection

Internal surfaces exhibited many rounded, mutually intersecting pits partially buried beneath silt, iron oxide, and sand deposits. Orange and brown corrosion products and deposits overlaid all. Sulfides were present in the deposits and corrosion products. The material was easily removed when acid was applied (Figs. 4.21 and 4.22). 

Tubes were removed for routine inspection. Internal surfaces had rough contours due to mutually intersecting areas of metal loss (Fig. 4.26). Wall thickness varied from 0.080 in. (0.20 cm) to as little as 0.032 in. (0.081 cm). 

Figure 4.26 Internal surface of steel heat exchanger tube after removal of deposits. Note the mutually intersecting areas of metal loss.

Figure 11.7 illustrates the internal surface at the inlet end of the condenser. Approximately 2 in. (5 cm) of the surface is marked by mutually intersecting depressions and grooves. Areas of the internal surface downstream of this zone are smooth and covered with a thin layer of deposits. This typical case of inlet-end erosion can be eliminated by the techniques discussed earlier in this chapter under Elimination. ... 

Cubic point groups have four threefold axes (3 or 3) that mutually intersect at angles of 109.47°. They correspond to the four body diagonals of a cube (directions x+y+z, -x+y-z, -x-y+z and x-y-z, added vectorially). In the directions x, y, and z there are axes 4, 4 or 2, and there can be reflection planes perpendicular to them. In the six directions x+y, x-y, x+z,. .. twofold axes and reflection planes may be present. The sequence of the reference directions in the Hermann-Mauguin symbols is z, x+y+z, x+y. The occurrence of a 3 in the second position of the symbol (direction x+y+z) gives evidence of a cubic point group. See Fig. 3.8. 

Figure 5.26. Iron binary alloys. Examples of the effects produced by the addition of different metals on the stability of the yFe (cF4-Cu type) field are shown. In the Fe-Ge and Fe-Cr systems the 7 field forms a closed loop surrounded by the a-j two-phase field and, around it, by the a field. Notice in the Fe-Cr diagram a minimum in the a-7 transformation temperature. The iron-rich region of the Fe-Ru diagram shows a different behaviour the 7 field is bounded by several, mutually intersecting, two (and three) phase equilibria. The Fe-Ir alloys are characterized, in certain temperature ranges, by the formation of a continuous fee solid solution between Ir and yFe. Compare with Fig. 5.27 where an indication is given of the effects produced by the different elements of the Periodic Table on the stability and extension of the yFe field.

On the phase diagram (Figure 23.3) the lines AD, BC and EF when extrapolated meet at a point labelled as the triple point, corresponding to one single specific temperature and one single specific pressure at which all three phases (solid, liquid and gas) will coexist and be equally stable (see Frame 50, section 50.4). This corresponds to the situation (at a specific pressure which we have labelled P ) where the curves of Gg, G and Gs versus temperature mutually intersect with one another. 

However, further mapping of the links showing all possible (so-called virtual) pathways for the mutual interconversion of clusters within a comprehensive operator network suggests that the classical systematics presented in Fig. 4.23 by no means cover ail the mechanisms of elementary substitution reactions. Indeed, what we have called the classical operator of substitution belongs not only to the methane molecule but also to any other cluster in the network, specifically to the CH cationic radical (Fig. 4.24a) and the CH7 anionic radical (Fig. 4.24b). In this case, however, upon mapping Figs. 4.23 and 24, it is evident that one can observe as it were an intranetwork of ""mutual intersection of the classical substitution mechanisms anresponding to all three entities (CH, CH and CH7). This then results in the formation of a series of... 

As schematically shown by Fig. 46a, ferrierite contains two mutually intersecting arrays of channels. In comparison with the strictly one-dimensional MOF crystals considered in the previous section, their analysis is additionally complicated by the existence of two rooflike parts on either side of the platelike main crystal body. It turned out, however, that these features did in no way complicate the method of analysis. Contrary to the MOFs, which required an additional activation step after each uptake experiment, methanol in ferrierite proved to be an ideal host-guest system, where one and the same crystal could alternately be subjected to adsorption and desorption without any perceptible change in the sorbate profiles. It were these special conditions under which interference microscopy could be developed to a technique of diffusion measurement in nanoporous materials of unprecedented power [63,65,70,71,88,89]. 

Equation (2.2-56) is most easily solved graphically by determining the mutual intersection (= operating point) of the S-shaped curve and the straight line as... 

Transversal internal waves generated by oscillating source (Fig. 1) have been obtained for the first time near the critical "liquid - vapour" point in which two mutually intersecting planes forming dihedron angle are phase surfaces. 

As a result of superposition of acts of this field of a corpuscle of dusty gas and an irrigating liquid, being propelled on a tangent to the curvilinear channel of breakdown pipes, gain a zigzag direction, and in different sections of the channel they have the path, that is, there is their repeated mutual intersection. At the expense of it the surface of eontact of phases increases and there is a process intensification. Having attained air swirlers... 

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