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Dartmouth Engineer - The Magazine of Thayer School of EngineeringDartmouth Engineer - The Magazine of Thayer School of Engineering


Yi-Heng Percival Zhang Th'02. Photograph courtesy of Josh Armstrong/Virginia Tech.
Yi-Heng Percival Zhang Th'02. Photograph courtesy of Josh Armstrong/Virginia Tech.

Esquire magazine has named Yi-Heng Percival Zhang Th’02 to its Best and Brightest 2006 list. Honored for his “crazy idea of the year: ‘sugar cars’ ” — their phrasing, not ours — Zhang has formulated a chemical process that can turn agricultural waste into cheap ethanol and, according to the magazine, possibly solve the “hydrogen puzzle” — the holy grail of alternative fuel.

The typical process of ethanol production uses corn kernels. Zhang’s approach leaves the kernels for food and instead uses the most abundant agricultural residue in the United States: corn stover (leaves, stalks, and cobs). And, rather than the high-cost, low-yield standard approach — blowing cells up under high pressures and temperatures to unlock the cellulose within the plant cell walls — Zhang thought to use a solvent. He and Thayer professor Lee Lynd Th’84 co-patented a recyclable biochemical pretreatment that generates cellulose that is more easily converted to sugar and doesn’t require special facilities.

An assistant professor of biological systems engineering in the College of Agriculture and Life Sciences at Virginia Tech since August 2005, Zhang began his research at Thayer, where he received his Ph.D. and worked as a postdoctoral research associate and research scientist. Zhang is now collaborating with the National Renewable Energy Laboratory and Oak Ridge National Laboratory, using NREL software to analyze the economic costs of various ethanol production strategies and ORNL facilities to test different enzymes and material performance. “We hope to soon establish the first pilot plant in Virginia based on this new technology with switchgrass,” says Zhang.

But the sweet spot for Zhang is hydrogen. His pretreatment process can cleanly deliver the high energy of the gas while avoiding the pollution, costly storage tanks, and infrastructure of standard technologies. He envisions “sugar cars” fueling up at “sugar stations,” which would allow a driver to pump solid sugar into the car’s tank; a converter would extract hydrogen from the sugar, and a fuel cell would convert the hydrogen to electricity. His recipe for making hydrogen from sugar: start with his ethanol-pretreatment process to release sugar from corn stalks, then add water, using the energy stored in those sugars in combination with a novel enzymatic system to divide the molecules into hydrogen and oxygen. So far he’s had high yields and modest reaction conditions. “We do not store and distribute gaseous hydrogen anymore. We can do it through solid sugars,” Zhang tells Esquire. “This new technology could change the whole world energy future completely.”

>> Good Dirt Radio in April profiled FrontRange Earth Force, a nonprofit service learning organization led by board president Kit Ambrose 86 Th90. “We work with teachers and nearly 2,000 students in the less-privileged areas of Denver, Colo. We teach teachers how to coordinate wonderful and innovative student-led projects that focus on solving community issues of the students’ choice,” says Ambrose, who works for Microsoft and is also on Thayer’s executive committee. “More than anything, my time at Dartmouth and Thayer helped with the desire to make a contribution and effect change as well as the confidence to participate.”

>> Hector J. Motroni ’66 Th’68 has earned a Dartmouth Alumni Award for his career accomplishments as well as extraordinary service to the College and civic organizations. Currently the senior vice president, chief staff officer, and chief ethics officer at Xerox Corp., where he has worked for the past 35 years, Motroni also chairs the Xerox Political Action Committee. He was recently named the National Hispanic Achiever of the Year by National Hispanic Corporate Achievers, Hispanic Trends magazine selected him one of the 25 top Hispanic executives, and Hispanic Engineer & Information Technology magazine included him on its list of “50 Most Important Hispanics in Business and Technology.” He has served Thayer as its representative on the Alumni Council; as secretary, vice president, and president of the Dartmouth Society of Engineers; and as a member of the boards of the Thayer School Dean’s Fund Executive Committee, the Thayer Campaign Executive Committee, and the Thayer Corporate Advisory Board.

>> recently asked top venture capital investors — including Amanda Reed ’86 — for great start up ideas. Reed is a partner in Palomar Ventures, a northern California-based VC fund in which she invests in early-stage technology companies with fellow alum Randy Lunn ’73 Tu’75 Th’75, a member of the Thayer Board of Overseers. says: “What she wants now: a Web-based platform to make company spreadsheets — for revenue forecasting and other analytical chores — more easily viewed, updated, and shared by managers. Many small-business execs still rely on e-mailing Excel files around the office to share data forecasts. Software apps like NetSuite import data but not the formulas embedded in spreadsheets. What she’ll invest: $5 million for a team of five engineers to create a prototype in less than two years.”

>> “Few can claim that they have revolutionized a sport as much as Judy Geer ’75 Th’83.” So reads the citation marking Geer’s induction last winter into the Choate Rosemary Athletics Hall of Fame. The first captain of the Dartmouth women’s rowing team, Geer spent the next decade pursuing honors. She was on both the national and Olympic teams in 1976, captured the national singles championship in 1979 and 1982, and joined the Olympic teams again in 1980 and 1984. But perhaps her greatest contribution to the sport came after she earned her Thayer degree: She developed software that displays motivational graphics and monitors performance for rowing machine company Concept 2. Now on the company’s marketing team, she and husband (and Concept 2 co-founder) Dick Dreissigacker are raising three children, including Hannah ’09.

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Categories: Alumni News, Spotlights

Tags: alumni, award, design, energy, patent, research

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