Constitution point

The state variables define a point on the diagram the "constitution point". If this point is given, then the equilibrium number of phases can be read off. So, too, can their composition and the quantity of each phase - but that comes later. So the diagram tells you the entire constitution of any given alloy, at equilibrium. Refer back to the definition of eonstitution (p. 311) and check that this is so. 

Which phases do you expect at each of the following constitution points, for the lead-tin system ... 

DEF. When the constitution point lies in a single-phase region, the alloy consists of a single, homogeneous, phase. Its composition must (obviously) be that of the alloy. The phase composition and the alloy composition coincide in single-phase fields. 

When the constitution point lies in a two-phase region the alloy breaks up into two phases which do not have the same composition as the alloy (though a properly weighted mean of the two compositions must equal that of the alloy). 

DEF. When the constitution point for an alloy lies in the two-phase field the alloy breaks up into a mixture of two phases. The composition of each phase is obtained by constructing the tie line (the isotherm spanning the two-phase region, terminating at the nearest phase boundary on either side). The eomposition of eaeh phase is defined by the ends of the tie line. 

To find the relative amounts of each phase, start off by constructing a tie line through the constitution point and read off the compositions of the phases (Fig. A1.15). 

Mark their constitution points onto the diagram at 200°C (not much happens between 200°C and room temperature). 

DMSO/isocyanate carbanilation medium on cellulose. It should be noted that the oxidation per se does not cause chain cleavage and cellulose degradation, but only the introduction of carbonyl functionalities along the cellulose chain. However, these groups constitute points of pronounced chemical instability where subsequent cleavage, mainly under basic conditions in /(-elimination processes, will readily occur. 

The obligatory establishment of joint offices (ARGEs) under 44b SGB II is highly problematic from a constitutional point of view. In particular, the administrative districts (Landkreise) saw the joint administration with the BA as an infringement of their constitutional guarantee of the municipalities autonomous... 

From the constitutional point of view, the employment of formic acid leads to interesting results, since hydride is site selectively transferred to the more hindered position of the allylic sulfone (Eq. 45).89 Thus, a hydride equivalent generated from formic acid is exceptional in this respect. It is proposed83 that decarboxylation and hydride transfer is a concerted process in which the hydride site selectively attacks the more substituted (more electropositive) side of the allylic system in a cyclic mechanism (SNi transfer of hydride, Scheme 1). 

Given the set of domain of grid points D, a subset 5 = s, of Z) is defined as constituting points that have less than six neighbors belonging to D. This is the surface set of grid points. The set S is then made independent of G and D, because the position of s, may be changed. 

Crystalline solids - in the case of crystalline sohds, we can no longer identify components and chemical species (atoms, ions or molecules), because the same species can occupy different sites in the crystalline lattice, which thus constitutes two different components. In addition, to take accoimt of some of the properties of solids, we also need to take accoimt of certain entities which appear to be irregularities in the arrangement of the species in space. These irregularities constitute point defects. We then define what is known as structure elements, and it is these which play the role of components. We are then led to the method used for ionic solutions. 

The monopole is simply the total charge of the constituting point charges ... 

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