10-09 :: September 2010

nanotimes News in Brief

David W. Keith examine in PNAS the possibility that engineered nanoparticles could exploit photo- phoretic forces, enabling more control over parti- cle distribution and lifetime than is possible with sulfates, perhaps allowing climate engineering to be accomplished with fewer side effects. The use of electrostatic or magnetic materials enables a class of photophoretic forces not found in nature. Pho- tophoretic levitation could loft particles above the stratosphere, reducing their capacity to interfere with ozone chemistry; and, by increasing particle lifetimes, it would reduce the need for continual replenishment of the aerosol. Moreover, particles might be engineered to drift poleward enabling albedo modification to be tailored to counter polar warming while minimizing the impact on equatorial climates. © PNAS

David W. Keith: Photophoretic levitation of engineered aerosols for geoengineering, In: PNAS, September 7, 2010, DOI:10.1073/pnas.1009519107: http://dx.doi.org/10.1073/pnas.1009519107

A group of scientists from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS), headed by D.Sc. Piotr Garstecki, constructed a microflow system allowing the streams of drops containing various solutions to merge. The new system makes it possible to produce and precisely control concentrations of reaction micromixtures, and it operates several times faster and with smaller volumes of liquids than the microtitre plate me- thod currently popular at laboratories. “The device developed by us will allow even tens of thousands of biochemical experiments to be conducted daily,” says Garstecki. The microlab may significantly affect

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the manner in which experiments are carried out with respect to chemical synthesis and medical dia- gnostics and biotechnologies.

Monika Pyzalska presents the microflow device constructed in the Institute of Physical Chemistry of the Polish Academy of Sciences. © IPC PAS

http://www.ichf.edu.pl/person/garstecki.html http://www.english.pan.pl/