Spontaneous patterns

Feinn, D., Ortoleva, P., Scalf, W., Schmidt, S. Wolff, M. (1978). Spontaneous pattern formation in precipitating systems. J. Chem. Phys., 69, 27-39. 

Classic Turing Models. The most well studied models of spontaneous pattern formation are based on Turing s original idea that symmetry breaking in biomorphogenesis occurs via an instability in a reaction-diffusion system. In order for this to be operative the time scales for reaction and diffusion must be comparable. Since cellular systems are in general quite small... 

Hubert C, Fiorini Debuisschert C, Maurin I, Nunzi JM, Raimond P. 2002a. Spontaneous patterning of hexagonal structures in an azo pol5uner using light controlled mass transport. Adv Mater 14(10) 729. 

Katsuragi, H. Diffusion-induced spontaneous pattern foimatirai rai gelation surfaces. Europhys. Lett. 73(5), 793-799 (2006)... 

Dendritic crystal growth is an example of spontaneous pattern generation in non-equilibrium systems. They are typically showing a tree-like branched microstructure which is exceptionally attractive for procedural and meticulous grounds. In contrast to multifarious biological systems, these types of patterns are attributing very common illustrations of self-organization [97-99] (Fig. 1.12). 

As a result of tip position control, a variety of shapes was derived. Before moving on to shape control, spontaneous pattern formation was studied. It was found them in simulation first, and discovered experimentally afterward. 

Spontaneous pattern formations are fundamental characteristics of systems under thermodynamically open conditions. Polymer gel of a cross-linked polymer network immersed in liquid shows rich spatiotemporal pattern formations since it is a typical open system exchanging its matter and energy with the surroundings [158]. Gel reversibly swells and shrinks when the external condition, such as temperature or solvent composition, varies[164, 200]. 

As already mentioned, dewetting leads to spontaneous patterning with spatial correlations, but a precise positioning of the individual structures is unlikely to occur across a very large area. A possible approach to overcome this limit relies on the spatial confinement of dewetting by means of an external agency, like a stamp. 

Rotaxanes, which are mechanically interlocked molecular architectures, are particularly interesting for their rich phenomenology of organization at a surface controlled by their intrinsic multistability. A series of rotaxanes and their respective threads were investigated. A spontaneous pattern formation occurs and... 

Heath discovered that hexane solutions of Ag nanoparticles, passivated with octanethiol, formed spontaneous patterns on the surface of water when the hexane was evaporated, " and has prepared superlattices of quantum dots. " Lieber has investigated the energy gaps in metallic single-walled carbon nanotubes and has used an atomic-force microscope to mechanically bend SWNT in order to create quantum dots less than 100 nm in length. He found that most metallic SWNT are not true metals, and that by bending the SWNT, a defect was produced that had a resistance of 10 to 100 kfl. Placing two defects less than 100 nm apart produced the quantum dots. 

Mazaheri, L., Ahmadi-Kandjani, S., Nunzi, J.M. Influence of temperature on the relaxation kinetics of spontaneous pattern formation in an azo-polymer film. Opt. Commun. 298-299, 150-153 (2013)... 

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