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MIT study: Hydrogen car no environmental panacea

Even with aggressive research, the hydrogen fuel-cell vehicle will not be better than the diesel hybrid (a vehicle powered by a conventional engine supplemented by an electric motor) in terms of total energy use and greenhouse gas emissions by 2020, says a study recently released by MIT’s Laboratory for Energy and the Environment (LFEE). And while hybrid vehicles are already appearing on the roads, adoption of the hydrogen-based vehicle will require major infrastructure changes to make compressed hydrogen available. If we need to curb greenhouse gases within the next 20 years, improving mainstream gasoline and diesel engines and transmissions and expanding the use of hybrids is the way to go.

Smart surface switches properties reversibly

MIT engineers and colleagues from the University of California are reporting a unique design of a “smart surface” that can reversibly switch properties in response to an external stimulus. The work paves the way for systems that could, for example, release or absorb cells and chemicals from surfaces on demand. In the Jan. 17 issue of Science, the researchers describe an example of their new approach in which they engineered a surface that can change from water-attracting to water-repelling with the application of a weak electric field. Switch the electrical potential of that field from positive to negative and the surface reverts to its initial affinity for water.

Aluminum shows strange behavior; research solves old mystery

Aluminum — one of nature’s best conductors of electricity conductors of electricity — may behave like a ceramic or a semiconductor in certain situations, according to an Ohio State University scientist and his colleagues. Among the findings that appear in the current issue of the journal Science: When it comes to forming tiny structures in computer chip circuits and nanotechnology, aluminum may endure mechanical stress more than 30 percent better than copper, which is normally considered to be the stiffer metal