Aggregate structure

Cellulose consists of several thousand o-glucose units linked by l- 4-/3-glyco-side bonds like those in cellobiose. Different cellulose molecules then interact to form a large aggregate structure held together by hydrogen bonds. 

I The quaternary structure describes how different protein molecules come together to yield large aggregate structures. 

Shuto, K., Oishi, Y, Kajiyama, T. and Han, C. C. (1993) Aggregation structure of a two-dimensional ultrathin polystyrene film prepared by the water casting method. Macromolecules, 26, 6589-6594. 

Reaction conditions can be modified to accelerate the rate of lithiation when necessary. Addition of tertiary amines, especially TMEDA, facilitates lithiation53 by coordination at the lithium and promoting dissociation of aggregated structures. Kinetic and spectroscopic evidence indicates that in the presence of TMEDA lithiation of methoxybenzene involves the solvated dimeric species (BuLi)2(TMEDA)2.54 The reaction shows an isotope effect for the o-hydrogcn, establishing that proton abstraction is rate determining.55 It is likely that there is a precomplexation between the methoxybenzene and organometallic dimer. 

Figure 7.13 Examples of bile salts and aggregate structures formed in aqueous solutions.

The native sample E (Fig. 3) contains a relatively large amount of aggregated structures. Most of them appear to rearrange into perfectly matched double-stranded chains after incubation at 80 °C for 2 months (27). This rearrangement is reported to result in a fivefold increase in the apparent viscosity at a shear rate of 1 s-1 (27). A similar rearrangement of xanthan assemblies is also observed in a unpasteurized fermentation broth after exposure of the sample... 

John, G., Jung, J.-H., Masuda, M. and Shimizu, T. (2001) Self-assembly of a sugar-based gelator in water its remarkable diversity in gelation ability and aggregate structure. Langmuir, 17 (23), 7229-7232. 

An important route to solubilization of carbon nanotubes is to functionalize their surface to form groups that are more soluble in the desired solvent environment. It has been shown that acid treatment of nanotube bundles, particularly with HC1 or HNO3 at elevated temperatures, opens up the aggregate structure, reduces nanotube length, and facilitates dispersion (An et al., 2004 Kordas et al., 2006). Nitric acid treatment oxidizes the nanotubes at the defect sites of the outer graphene sheet, especially at the open ends (Hirsch, 2002 Alvaro et al., 2004), and creates carbonyl, carboxyl, and hydroxyl groups, which aid in their solubility in polar solvents. 

Corresponding approaches were developed in all the research methods theoretical, computer simulation, and, moreover, experimental. Thus, copolymers were synthesized in vitro, which form non-aggregating structures of the type hydrophobic core-hydrophilic shell. The structure of such copolymers is similar in this respect to that of protein macromolecules [125-127]. 

The examples cited in this chapter are but a rather small and arbitrary selection from the richly varied possibilities for supramolecular bonding. Recognition of the intrinsic chemical (partially covalent, exchange-type) character of supramolecular interactions leads inevitably to an extended definition of chemistry that includes many aspects of nanoscale aggregation, structure, and function in the biophysical and material-science domains. From this viewpoint, the molecule is seen to be... 

Novel concepts of aggregation structure of fatty acid monolayers on the water surface... 

Electron microscopic studies of aggregation structure in monolayer. 

Surface aggregation structure of the monolayer based on gold decoration technique... 

THE EFFECT OF IONIC REPULSION AMONG HYDROPHILIC GROUPS ON THE AGGREGATION STRUCTURE OF MONOLAYER... 

Aggregation structure of arachildic acid monolayer in a dissociated state. 

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