News Service

July 1999

News about Science, Technology and Engineering at Iowa State University

New technique allows faster identification of ultratrace metals

A novel extension of inductively coupled plasma-mass spectrometry (ICP-MS), an analytical technique pioneered at the Department of Energy's Ames Laboratory at Iowa State, is making the identification of ultratrace metals in biological systems easier. Developed by senior chemist Sam Houk, the combination of ICP-MS with the separation techniques of chromatography allows measurements down to parts-per-trillion levels. The new method also is faster, more sensitive and more selective than conventional techniques. The measurements help scientists better comprehend the effects of both radioactive and nonradioactive elements in biology and environmental sciences.

"Since the DOE has radioactive elements in storage, monitoring their binding to proteins and DNA at very low concentrations is of great environmental importance," Houk says. For more information, contact Houk, (515) 294-9462, or Saren Johnston, Ames Lab Public Affairs, (515) 294-3474.

Recycled railroad cars bridge a money gap

Terry Wipf and Wayne Klaiber, Iowa State University civil and construction engineering professors, are looking into the feasibility of using retired railroad flatcars as replacement bridges on low-volume roads.

"Counties generally have very limited budgets and a significant number of bridges they would like to replace," Wipf said. "So, they are always looking for good, cost-effective alternatives. All we have to do is remove the wheels from railroad flatcars and they can serve as a bridge's super structure. This would be a quick and inexpensive alternative to building a new bridge."

A few companies have stockpiled retired flatcars, which are in sound structural condition. "They were retired because the new-generation flatcars haul more cost-effectively," said Wipf. The Iowa Department of Transportation awarded the researchers nearly $72,000 to determine the feasibility of using the flatcars, and they are testing one of their bridges in Tama County, Iowa. For more information, contact Wipf, (515) 294-6979; Klaiber, (515) 294-8763; or Mitch Mihalovich, Engineering Communications, (515) 294-4344.

Iowa State wins two national technology awards

A method for converting waste-water sludge into useful biosolid materials and a genetic testing technique to determine which pigs will have the largest litters have won 1999 R&D 100 Awards. The two new R&D 100 Awards, sponsored by R&D Magazine, bring Iowa State's total to 21 awards since 1984. The R&D 100 Awards are the only awards for applied science and scientists.

One R&D 100 Award is in honor of the work of ISU civil and construction engineering professor Richard Dague (Dr. Dague died in 1996), who developed a temperature-phased anaerobic digestion process. The TPAD process can more efficiently convert municipal waste sludge into environmentally safe and beneficial biosolids. The TPAD process provides a solution to long-standing problems of dealing with waste-water sludge. TPAD is inexpensive and efficient in converting the sludge to biosolids that meet federal (Class A) biosolids standards for unrestricted land application. It also produces a biogas that contains 60 to 75 percent methane as a viable energy product. The technology has been licensed to Anaerobic Biosystems Corp., Ames, Iowa.

The second R&D 100 Award is for an estrogen receptor (ESR) gene test for improved pig litter size. It was developed by Iowa State animal geneticist Max Rothschild, and is a genetic testing method that helps pork producers increase the size of pig litters by scientifically identifying which females and males have the genes to produce larger litters. Rothschild and his colleagues found that pigs with both copies of a desirable form of estrogen receptor gene have 0.8 to 0.9 more pigs per litter on average than sows without this advantage. Using this test in a 1,000 sow operation could mean a $20,000 increase in income based on average pork prices, Rothschild said. The technology has been licensed to PIC International Group, Berkeley, Calif.

For more information on TPAD contact Ellis, (515) 294-8922; on the ESR test contact Rothschild (515) 294-6202; or Skip Derra, News Service, (515) 294-4917.

Putting together guidelines for welds

As scientists and technicians at Iowa State's Center for Nondestructive Evaluation listened to the questions raised by manufacturers, a recurring one involved how to nondestructively inspect spot welds in assembly shops. Spot welds are used in everything from office equipment to refrigerators and automobiles.

"Although there is extensive research published on inspecting spot welds, many small manufacturers, as well as large firms, need tangible guidelines for applying known techniques to their welds," said Brian Larson, program director of CNDE's Iowa Demonstration Laboratory.

As a result, IDL joined forces with five Iowa manufacturers, under the direction of researcher Dave Utrata, to develop guidelines for "best practice" technologies in industry. Samples were solicited from manufacturers, and IDL used various nondestructive inspection techniques on spot welds to evaluate them for efficacy and ease of use. The result is a set of guidelines for two nondestructive inspection techniques -- micro-resistive and ultrasonic. These guidelines are now available on the Web at For more information, contact Larson, (515) 294-8158; Utrata, (515) 294-6095; or Anita Rollins, IPRT Public Affairs, (515) 294-1113.

- 30 -

Iowa State homepage

University Relations,
Copyright © 1999, Iowa State University, all rights reserved