Non-lamellar solids

TABLE 19-13. SOME NON-LAMELLAR SOLIDS STUDIED AS LUBRICANTS... 

A serious difficulty in developing theoretical models for electroactivity at films like those described above, is the heterogeneity and random distribution of particle sizes. In addition, the means of holding solid particles to the surface of an electrode can interfere with charge transport in a way that is difficult to describe mathematically. Films of colloidal clay particles can be cast to form smooth, rather robust films, but non-lamellar solids and larger particles are not as easily held at the surface of an electrode. Improvements in this area are discussed below. 

LUBRICATION BY NON-LAMELLAR INORGANIC SOLIDS AND BY SOFT METALS... 

Despite intensive research, the structural arrangements of Rf-Rh diblock molecules in their solid sate and LC structures remain largely hypothetical as XRD patterns provide too small a number of reflections to prove unambiguously the proposed structures [66], The present state of knowledge in this field was recently reviewed by Krafft and Riess [66] and therefore will not be discussed in detail here. Only four representative examples of non-modulated lamellar structures are shown in Fig. 6a-d the two models on top were proposed for the LC1 (high temperature phase = HT) and LC2 (low temperature phase = LT) phases of CioH2i-CioF2i [102] and those shown in Fig. 6c,d were obtained by Monte-Carlo... 

Typical surfactant-water-phase diagrams are shown in Fig. 3.4 for single-chained ionic, and non-ionic surfactants respectively. Below a "Krafft" temperature characteristic of each surfactant, the chains are crystalline and the surfactant precipitates as a solid. Increased surfactant concentration (Fig. 3.4) results in sharp phase boundaries between micellar rod-shaped (hexagonal), bilayer (lamellar) and reversed hexagonal and reversed micellar phases. (The "cubic" phases, bicontinuous, will be ignored in this section and dealt with in Chapters 4,5 and 7.)... 

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