June 1999

News about Science, Technology and Engineering at Iowa State University

Bridging the gap

Surya Mallapragada, an Iowa State University assistant professor of chemical engineering, is developing a method of stimulating nerve growth that borrows from technology used in computer chip fabrication.

"When the gap between a severed nerve is too large, it's very difficult for the nerve to regenerate, or grow back together," she said. "The current medical practice is to take a nerve section from another part of the body to fill in the gap. Our research will help to eliminate that step."

Mallapragada and her colleagues are using tube-like polymer substrate structures, which act as a bridge to guide the nerves back together. These structures, which have micro- and nano-patterned grooves lining the polymer substrates, as well as the inclusion of other cells, will speed up directional nerve growth. For more information, contact Mallapragada at (515) 294-7407, or Mitch Mihalovich, Engineering Communications, (515) 294-4344.

Summer training for women scientists from developing nations

Iowa State University is the summer home to 20 women scientists from several developing and Eastern European nations. The International Women in Science and Engineering (IWISE) summer workshop will help these women scientists by providing them with research and networking opportunities with their peers in the West. It is the only program of its type in existence, said Mary Ann Evans, IWISE co-director.

"The IWISE summer workshop gives its participants the chance to work in well-equipped labs, to meet and exchange ideas with scientists in their fields and to take in our culture," Evans said. "Some of our participants have taken what they learned in the program and really opened doors for themselves in their home countries."

Women taking part in the eight-week program, which runs through Aug. 6, include those from the Ukraine, Lithuania, Russia, Botswana, Nigeria, Kenya, Armenia and Columbia. For more information, contact Evans at (515) 294-5883, or Skip Derra, Â鶹´«Ã½ Service, (515) 294-4917.

Magnetic-refrigeration moves to prototype stage

Every time researchers Karl Gschneidner Jr. and Vitalij Pecharsky tell someone about magnetic-refrigeration technology, they hear the same question. "Where can I see it?" For the past few years, the scientists at the U.S. Department of Energy's Ames Laboratory and Iowa State's Materials Science and Engineering Department have patiently explained that they haven't had the funding to build a working prototype. But that's about to change.

Ames Laboratory and Milwaukee-based Astronautics Corp. of America have signed a three-year agreement to build a prototype rotary magnetic-refrigeration unit. If successful, the prototype would be the first magnetic refrigerator capable of sustained operation and generating enough cooling power for commercial applications.

The technology is based on the magnetocaloric effect -- the ability of some materials to heat up when magnetized and cool down when removed from the magnetic field. Using these materials as refrigerants would provide an environmentally friendly alternative to volatile liquid chemicals, like chlorofluorocarbons and hydrochlorofluorocarbons, used in traditional vapor-cycle cooling systems.

The Ames Lab scientists will concentrate their efforts on optimizing the performance of the alloys, and developing a source for the magnetic field that is more cost-effective and convenient than superconducting magnets. Astronautics will design, build and test the rotary prototype. For more information, contact Gschneidner at (515) 294-7931, or Susan Dieterle, Ames Lab Public Affairs, (515) 294-1405.

Coal research grants awarded to ISU Iowa State University has been awarded two University Coal Research Grants from the U.S. Department of Energy to improve hot gas clean up in coal plants. ISU's Center for Sustainable Environmental Technologies (formerly the Center for Coal and the Environment) received $400,000 for the two projects. Research will be conducted by faculty in the departments of Mechanical Engineering, Chemical Engineering, and Materials Science and Engineering.

ISU is the only university to have been awarded two grants, both of which are "core program" grants that support the DOE's goal of improved efficiency and cleanliness of coal burning operations. The grants both concern hot gas contaminant and particulate removal techniques, areas where improvement is needed because current methods limit a plant's efficiency.

The first project will get $200,000 from the DOE and $122,311 from ISU to study the formation of dust cakes and improve the performance of moving bed granular filters for hot gas clean up. Robert Brown and Gerald Colver are co-principal investigators of the work.

The second project ($200,000 from the DOE and $103,076 from ISU) will focus on methods for producing a regenerable, superior calcium-based sorbent for cleaning up hot gas in integrated combined-cycle systems. Thomas Wheelock, L. K. Doraiswamy and Kristen Constant are the co-principal investigators on this project. Contact Brown at (515) 294-7934; Wheelock at (515) 294-5226; or Matt Voss, IPRT Communications, (515) 294-5635.

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