Nanocosmos

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Nanocosmos , based on the term microcosm - for the microscopic world that is observed through a light microscope - denotes the thousand times smaller world of cells and macromolecules ( proteins , DNA ), whose dimensions are typically in the range of nanometers (millionths of a millimeter). The creation of artificial systems that operate in this size range is the subject of nanotechnology .

Characteristics

Several characteristic properties distinguish the nanocosm from the microcosm on the one hand, and the world of atoms dominated by quantum physics on the other:

  • Objects with dimensions that are smaller than the wavelength of visible light (400–800 nm) cannot be captured with the light microscope for fundamental physical reasons, so they are “invisible” in contrast to the microcosm. Any visual representations that can be created from them are, in principle, models and not images.
  • Mechanical motion on this scale is governed by the randomly distributed Brownian motion , which requires a different type of machine than Newtonian mechanics , which prevails on larger scales. Molecular machines in the nanocosmos therefore do not work according to a clear cause-and-effect concept such as a pendulum clock, but according to mechanisms that allow certain random movements and exclude others.
  • Surface tension is stronger on the nanometer scale than z. B. Gravitation , which can lead to considerable problems when mixing liquids (nanofluidics), for example.
  • Access to the nano-cosmos has long been a challenge for research, as this size range is too large for traditional organic-chemical synthesis , but on the other hand too small for material processing methods that start from large structures and reduce them. Since the beginning of this century, however, research has made far-reaching advances that have improved the accessibility of nanostructures from both sides.
  • The term “nanocosmos” also emphasizes that these and other characteristics apply both to natural systems (e.g. from the interior of the cell) and to artificial systems (i.e. products of nanotechnology, which has grown rapidly in recent years). The smallness of these objects is often more decisive for their properties than their exact composition or their origin.

Concept history

The term was used in 1995 in the book title "Expeditions into the nanocosmos". This book contrasted natural and synthetic nanosystems and emphasized that we can learn from the established "nanotechnology of nature" when developing new concepts in nanotechnology. At the turn of the millennium, he also appeared in popular magazines such as Der Spiegel. In English, “nanoworld” has established itself as a corresponding term.

Web links

Individual evidence

  1. ↑ a b M. Groß, Expeditions in den Nanokosmos, Birkhäuser Verlag, Basel, 1995
  2. ↑ D. Goodsell, Bionanotechnology, Wiley-Blackwell 2004
  3. ↑ RD Astumian, Scientific American January 2002 Molecular Motors
  4. ^ J. Edel, AJ De Mello, Nanofluidics: Nanoscience and Nanotechnology, RSC Publishing 2008
  5. ↑ a b Vincenzo Balzani , A. Credi, M. Venturi, Molecular Devices and Machines: Concepts and Perspectives for the Nanoworld, Wiley-VCH 2008
  6. ^ M. Haw, Middle World, Palgrave / Macmillan 2006
  7. ↑ DER SPIEGEL - April 17, 2000: DIVING IN THE NANOCOSM The world in the 21st century (part 3): Medical technology - mini-submarines circling through veins and cells
  8. ↑ A. Wixforth, Surfing in the nano-cosmos of physics in our time 1999, Volume 30, No. 3, Pages: 23–130