How nanoparticles influence earth chemistry
An example of the impact of nanoparticles is how they nurture ocean-dwelling phytoplankton, which removes carbon dioxide from the atmosphere. Phytoplankton growth is limited by iron availability, the authors report, citing research by J. Wu, E. Boyle, W. Sunda, L.S. Wen, and B.A. Berquist in two articles from 2001 and 2007. Iron in the ocean is composed of nanocolloids, nanominerals, and mineral nanoparticles, which is supplied by rivers, glaciers, and atmospheric deposition. Nanoscale reactions resulting in the formation of phytoplankton biominerals such as calcium carbonate are also important influences on oceanic and global carbon cycling.
Another example is the movement of harmful heavy metals in the Earths critical zone. In ongoing research at the Clark Fork River Superfund Complex in Montana, Hochellas group discovered a nanocrystalline vernadite-like mineral (a manganese oxyhydroxide) involved in the movement of lead, arsenic, copper, and zinc hundred of miles in the river drainage basin. Radionuclides can also be moved, the review reports. Research by A.P. Novikov (2006) at one of the most contaminated nuclear sites in the world, a nuclear waste reprocessing plant in Mayak, Russian, has shown that plutonium has traveled in local groundwater, carried by nanoparticles of less than 15 nanometers.
In the atmosphere, nanoparticles impact heating and cooling. The characteristics of atmospheric nanoparticles is critical and is now being studied by a large number of scientists. One observation is that such particles act as water drop growth centers, which is critical to cloud formation. The size and density of droplets dictates solar radiation scattering ability and cloud longevity, which influence average global temperatures.
The authors conclude that The
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