NEWS OF THE WEEK SPACE
BUSH CALLS FOR RETURN TO MOON Plan will focus space station research on effects of space on human biology
P
RESIDENT GEORGE W. BUSH
unveiled his vision for the future ofhuman space travel at NASA headquarters on Jan. 14. The plan, "A Renewed Spirit of Discovery," provides the agency with a new focus and goals. "Inspired by all that has come before, and guided by clear objectives, today we set a new course for America's space program," Bush told NASA employees. In his plan, Bush calls for NASA to return the shuttle to flight so that the International Space Station (ISS) can be completed by 2010, at which time the shuttle will be retired. NASA will also refocus
MATERIALS
the ISS research with the "primary almost singular" emphasis on the study of the effects of space travel on human biology NASAAdministrator Sean O'Keefe said. "Physical and chemical research that was planned for the space station will clearly take second priority to life sciences," says John M. Logsdon, director of the Space Policy Institute at George Washington University, Washington, D.C. The second part of the plan is for NASA to develop, test, and have operational the Crew Exploration Vehicle to carry astronauts to ISS and beyond by
SCIENCE
RIGID POLYMERS PACKED WITH PORES Macromolecular microporous solids have exceptionally high surface areas
A
FAMILY OF POLYMERS RID-
dled with nanosized pores could be used in separation and adsorption processes and in heterogeneous catalysis, according to the chemists in England who developed the materials. Dubbed "polymers of intrinsic microporosity" (PIMs), they are synthesized from commercially available starting materials. The work was carried out by reader in chemistry Neil B. McKeown, senior lecturer in chemistry Peter M. Budd, and coworkers at the University of Manchester [Chem. Commun., 2004,230]. H T T P : / / W W W . C E N - 0 N Ll N E . O R G
"The microporosity originates from the highly rigid and contorted molecular structures of the polymers, which prohibit close packing of the macromolecules in the solid state," McKeown tells C & E N . "The presence of interconnected micropores with an average diameter of 0.5 nm results in remarkably high surface areas." Unlike conventional microporous materials —zeolites or activated carbons, for example—PIMs are soluble and can be cast into thermally stable films suitable for use as sepa-
2014. The final component of the plan is to return to the moon and establish a lunar base by 2020. From this base, future missions, such as human trips to Mars, will be launched. The initial cost ofthe President's plan will be $12 billion over a fiveyear period. NASA will reallocate $11 billion from its current fiveyear budget of $86 billion and request an additional $1 billion in new appropriations over the pe-
HIGHER CALLING Astronaut C. Michael Foale greets Bush from ISS at the start of the President's news conference.
riod.-SUSAN M0RRISSEY
ration or reactive membranes. "The solubility also allows a PIM to be used as a microporous matrix for the support of a homogeneous catalyst simply by casting a solution containing both polymer and catalyst, thereby entrapping the catalyst within its micropore structure," McKeown says. "The nature of the accessible surface is determined by the choice of the monomer precursors. Bespoke [custom-made] PIMs can therefore be prepared for chemoselective catalysis, separation, or adsorption, and it will be possible to introduce chirality for enantiomeric processes." The Manchester chemists have shown that PIMs can be fabricated into robust, freestanding films that can be used as membranes for removing organic compounds like phenol from water. The group is also planning to investigate the use of PIMs as selective adsorbents for toxic and malodorous compounds.-MICHAEL FREEMANTLE C & E N /
CONTORTED Shape of macromolecule prevents efficient packing. JANUARY
1 9,
2004
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