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Self-assemblySelf-assembly is the fundamental principle which generates structural organization on all scales from molecules to galaxies. It is defined as reversible processes in which pre-existing parts or disordered components of a preexisting system form structures of patterns. Self-assembly can be classified as either static or dynamic. Static self-assembly is when the ordered state occurs when the system is in equilibrium and does not dissipate energy. Dynamic self-assembly is when the ordered state requires dissipation of energy. Examples of self-assembling system include weather patterns, solar systems, histogenesis and self-assembled monolayers. The most well-studied subfield of self-assembly is molecular self-assembly, but in recent years it has been demonstrated that self-assembly is possible with micro and milimeterscale structures lying in the interface between two liquids. Molecular self-assembly Molecular self-assembly is the assembly of molecules without guidance or management from an outside source. There are two types of self-assembly, intramolecular self-assembly and intermolecular self-assembly, although in some books and articles the term self-assembly refers only to intermolecular self-assembly. Intramolecular self-assembling molecules are often complex polymers with the ability to assemble from the random coil conformation into a well-defined stable structure (secondary and tertiary structure), an example of intramolecular self-assembly is protein folding. Intermolecular self-assembly is the ability of molecules to form supramolecular assemblies (quarternary structure). Self-assembly can occur spontaneously in nature, for example in cells (such as the self-assembly of the lipid bilayer membrane) and other biological systems, as well as in human engineered systems. It usually results in the increase in internal organization of the system. Also, self-assembly is a manufacturing method used to construct things at the nanometre-scale. Many biological systems use self-assembly to assemble various molecules and structures. Imitating these strategies and creating novel molecules with the ability to self-assemble into supramolecular assemblies is an important technique in nanotechnology. Self-assembly involves a chemical process called convergent synthesis. Microchips of the future might be made by molecular self-assembly. An example of self-assembly in nature is the way that hydrophilic and hydrophobic interactions cause cell membranes to self assemble. See also External links and references
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