Amphiphile homologous

Sodium a-sulfonated fatty acid esters of long-chain alcohols have a structural effect on the Krafft point different from that of amphiphiles with short alkyl chains [60]. In a series of homologs with the same total carbon number the Krafft points are highest when the hydrophilic alkyl chain lengths in the a-sulfonated fatty acid and the alcohol are fairly long and equal. In this case the packing of the molecules becomes close and tight. 

In this study, we demonstrated that high orientational order of a polar azobenzene-linked amphiphile was introduced to monolayers by means of the molecular mixing with a homologous amphiphile. Further, enhancement of SHG was observed in the mixed monolayer owing to the improvement of orientation of polar molecules. The mixing technique is expected to develop the construction of noncentrosymmetric LB films with highly efficient optical nonlinearity. 

To obtain additional evidence in support of this hypothesis, three peptides were designed to be capable of forming a basic, amphiphilic a helix but to share little sequence homology with any natural calmodulin-binding peptide (Cox et al., 1985). The first two synthetic peptides, CBP1 and... 

Musso et al., 1983, 1984), vasoactive intestinal peptide (G. Musso, personal communication), growth hormone-releasing factor (Tou et al., 1986 Velicelebi et al., 1986), and calcitonin (Moe et al., 1983 Moe and Kaiser, 1985). In each of these cases, highly active analogs were produced by replacing a portion of the peptide sequence with a model amphiphilic a-helical sequence that had minimal homology to the parent hormone. 

The surface activity of the surfactant is related to its amphiphilic properties. The longer the hydrocarbon chain of a homologous series of surfactants, the greater the... 

The hydrophobic interactions are known to control many aspects of self-assembly and stability of macromolecular and snpramolecular structures. This has obviously been useful in both theoretical analysis and technical development of chemical structures. Furthermore, the interaction between nonpolar parts of amphiphiles and water is an important factor in many physicochemical processes, such as surfactant micelle formation and adsorption or protein stability. To make the discussion short, this interaction will be discussed in terms of the measured data of the surface and interfacial tension of homologous series. Analyses have shown that there is no clear correlation therefore, different homologous series will be discussed separately. 

Elemental sulfur is an extremely hydrophobic material and the same holds for sulfur-rich compounds R-S -R with hydrophobic organic terminal groups R like alkyl or aryl. However, strongly hydrophihc groups Hke -SOs" are able to turn these hydrophobic substances into hydrophihc materials even at very high sulfur contents. Sulfane disulfonate anions S (S03)2, better known as polythionate anions, are such species which quahfy for amphiphilic behavior in water. These ions exist as a long homologous series with n... 

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