This diagram shows the size of objects from protons to the earth, with a logarithmic scale in meters. The diagram incorporates observations from chemistry, biology, geology, and physics. A quick sample of observations that arise from it include . . .|
The minimum size of biological entities. The width of DNA strands must be about an order of magnitude greater than ionic radii, the size of a bundle of DNA (a virus) must be yet an order of magnitude larger, and the size of an organism containing a bundle of DNA plus metabolic material (a small prokaryote) must be about another order of magnitude larger still. Organisms in the range of tens of nanometers are therefore improbable.Notes and sources:
Notes regarding small colloidal particles:
Thickness of double layer in solution: Berner (1980) Chemical Sedimentology and Appelo and Postma (1994) Geochemistry, Groundwater, and Pollution.
Small magnetite and periclase crystals: http://www.psrd.hawaii.edu/May02/ALH84001magnetite.html.
Lipids: ridge.icu.ac.jp/gen-ed/ eukaryotic-cell.html.
Thickness of altered mineral surface layers: Wollast and Chou (1984. in Drever. ed., Chemistry of Weathering; Hellman et al. (1990) as cited in Hochella (1990) p. 99-100 in MSA Review in Mineralogy Volume 23: MIneral-Water Interface Geochemistry.
Viruses and Chromosomes: Campbell et al., Biology, p. 320 and 325.
Largest prokaryotic and eukaryotic cells: http://www.globaldialog.com/~jrice/algae_page/valonia.htm and http://www.eurekalert.org/pub_releases/1999-04/AAft-BBEF-160499.php
Gold cluster compunds: J. F. Hainfeld, R. D. Powell, F. R. Furuya, and J. S. Wall , 2000, Gold Cluster Crystals: Microsc. Microanal., 6, (Suppl. 2: Proceedings) (Proceedings of the Fifty-Eighth Annual Meeting, Microscopy Society of America); Bailey, G. W.; McKernan, S; Price, R. L.; Walck, S. D.; Charest, P.-M., and Gauvin, R., Eds.; Springer-Verlag, New York, NY, 2000, pp. 326-327. (see http://www.nanoprobes.com/MSAXTALS00.html) The size estimate shown on the figure is Railsback's estimate for the Au6 compound.
Responses of matter with absorption of electromagnetic radiation: Figure 1 of Calas, G., and Hawthorne. F.C., 1988, Introduction to spectroscopic methods, in Hawthorne, F.C. ed., Spectroscopic Methods in Mineralogy and Geology: Mineralogical Society of America, Reviews in Mineralogy v. 18, p. 1-9.
The filtration spectrum: http://www.osmonics.com/products/refpage/zoomfiltspec.htm
Buckyballs and wave properties:
X-ray lasers: Kapteyn and Ditmire (2002) Ultraviolet upset: Nature v. 420, p. 467-468.
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