Out With Polluted Particles and Gases
Hydrogel air cleaners do double duty.
A newly invented, inexpensive hydrogel does double-duty removing pollutants from indoor air and might one day be available commercially.
photo by Stanley Leary The hydrogel air cleaner developed at the Georgia Tech Research Institute removes both particles and volatile organic compounds from air that is filtered through it.
Known as the hydrogel air cleaner, the gel removes both particles and volatile organic compounds from air that is filtered through it, explains principal research scientist Charlene Bayer of the Georgia Tech Research Institute (GTRI). She and Dr. Jan Gooch, a polymers and coatings consultant, invented and patented the substance.
"Other air cleaning media remove either particles or gases, but not both," says Bayer, of GTRI's Electro-Optics, Environment and Materials Laboratory. "In addition, the hydrogel air cleaner doesn't support microbial growth. Microbes growing on other kinds of filtering materials can emit volatile organic compounds, aggravating indoor air quality problems."
Hydrogels are essentially chains ofw simple molecules, many of them water. The gels demonstrate solid and liquid qualities, making them useful in many applications from repairing internal body parts to absorbing moisture in diapers.
Preliminary studies show that the prototype hydrogel air cleaner removes 50 percent of respirable-size airborne particles, and 80 to 90 percent of gaseous air pollutants. Some other air cleaning media do remove a greater percentage of particles or similar amounts of gases from the air compared to the hydrogel air cleaner. But these media absorb either particles or gaseous materials not both. And some also may provide fertile ground for microbe growth.
The preliminary studies were conducted by fashioning the hydrogel into a filtering mesh, and also by applying it directly to existing furnace air filters.
The hydrogel air cleaner works via absorption and adsorption, but the exact mechanism is a mystery even to Bayer, who plans to continue exploring the workings of the gel.
With funding from the Faculty Research Commercialization Program through Georgia Tech's Advanced Technology Development Center, the researchers have worked to move the hydrogel air cleaner closer to a commercial product. Bayer and her colleagues would eventually like to develop the hydrogel into a form that could substitute for the standard air filter in building, vehicle and military applications. They also want to improve the lifetime of the hydrogel air cleaner, incorporating enough of the substance into a filtering device to make it competitive with the three-to-six months minimum lifetime of standard air filters.
For more information, you may contact Charlene Bayer, Electro-Optics, Environment and Materials Laboratory, Georgia Tech Research Institute, Atlanta, GA, 30332-0820. (Telephone: 404/894-3825) (E-mail: email@example.com)
Quality Air in the Classroom
Study is investigating active humidity control in schools.
Your kids spend most of their day at school so how good is the indoor air quality in their classrooms?
The answer could depend on whether certain climate control technologies are used in their schools, says principal research scientist Charlene Bayer of the Georgia Tech Research Institute (GTRI). Bayer is leading a study that examines the effects of continuous active humidity control and ventilation on schools' indoor air quality.
Photodisc photo Georgia Tech Research Institute researchers are studying the effects of continuous active humidity control and ventilation on schools' indoor air quality.
"Our hypothesis is that if schools have active humidity control, the air quality will be better thus, the learning environment will be improved, and student learning will be enhanced," says Bayer, who conducts research in GTRI's Electro-Optics, Environment and Materials Laboratory.
The results of the study could be an important part of school modernization and construction efforts around the country, Bayer says. Many indoor air quality issues affect children more dramatically than adults.
"Children are generally more susceptible to respiratory ailments," she says. "Asthma, which is increasing among children, is linked to indoor air quality problems particularly molds, moisture and dust mite feces. Dust mites are prolific in areas of high humidity."
The study is one of only a few statistically controlled, quantitative studies of school air quality ever conducted. It is sponsored by the U.S. Department of Energy via humidity control systems manufacturer SEMCO Manufacturing Inc.
Researchers have divided the 10 participating Georgia schools four in metro Atlanta and six in high-humidity coastal regions into five pairs. Each pair of schools is similar in design, building age, mechanical systems and location. But only one school in each pair uses active humidity control technology. Any significant impact of active humidity control on air quality will be readily apparent, Bayer says.
Researchers are tracking carbon dioxide, temperature, humidity, airborne and surface microbes, and microbial emissions of volatile organic compounds. They are taking measurements at each school in fall, winter and spring, and have set up continuous monitoring devices on site. Unlike previous studies, this work avoids schools with known air quality problems.
"We specifically did not take schools with problems for this study so we could get good, baseline data," Bayer says.
The active humidity control systems used by participating schools are manufactured by several different vendors, to prevent vendor bias from affecting the study's results.
Georgia Tech's School of Earth and Atmospheric Sciences will perform particle analysis. Dr. Sidney Crow of Georgia State University's Department of Biology will analyze microbial findings.
Students at participating schools also will benefit intellectually from the study. Researchers are teaching them about research, sampling and scientific method related to the project. Youngsters are monitoring air quality measuring devices at their schools, and they chart their data with help from the researchers via an Internet site.
The study will be completed at the end of spring 1999, with results available at the end of summer 1999. The researchers are interested in expanding their work to other states.
Lea McLeesFor more information, you may contact Charlene Bayer, Electro-Optics, Environment and Materials Laboratory, Georgia Tech Research Institute, Atlanta, GA, 30332-0820. (Telephone: 404/894-3825) (E-mail: firstname.lastname@example.org)
National Science Foundation establishes first tissue engineering center at Georgia Tech.
The next generation of medical implants is one step closer to reality, with the awarding last fall of a $12.5 million grant from the National Science Foundation to the Georgia Institute of Technology. The grant established the first Engineering Research Center for the Engineering of Living Tissues at Georgia Tech, with Emory University as a core partner institution.
photo by Billy Howard Dror Seliktar, a Georgia Tech graduate student, prepares tissue-engineered vascular grafts. The research focuses on ways to grow artificial veins for use in bypass surgery, eliminating the need to use veins taken from patients' legs. The artificial veins will be stronger and less likely to clog than veins taken from a patient.
Tissue engineering research may soon produce advances in the regulation of blood glucose for diabetics, the regeneration of bone to correct genetic defects, and the creation of bioartificial blood vessels for high risk heart patients, Georgia Tech researchers say.
The National Science Foundation (NSF) is funding the one-of-a-kind Engineering Research Center (ERC) with $12.5 million over the first five years, with a potential duration of 10 years. The center is conducting research on the design and development of tissue substitutes that replace, enhance or maintain natural tissue. Dr. Robert M. Nerem, director of Georgia Tech's Petit Institute for Bioengineering and Bioscience, is also director of the ERC.
"Tissue engineering represents the next generation of medical implants, and this award allows us, working with our industrial partners, to take the lead in harnessing the products of the biological age and to revolutionize this important industry," Nerem says.
The ERC is focusing on specific research projects in three core areas: cell technology, cell construct technology (prototype organ or tissues structures) and their integration into living systems. Current research projects in tissue engineering include: the development of substitute blood vessels; the creation of a bioartificial pancreas; and engineering bone repair.
After years of maintaining a grassroots collaborative relationship, Georgia Tech and Emory University signed formal agreements to establish a biomedical research program in the mid-1980s. In the fall of 1997, in a pioneering academic collaboration, the two institutions established a joint department of biomedical engineering, creating Georgia's and possibly the nation's first joint department between a public and private university. Both the new research center and the Georgia Tech/Emory Department of Biomedical Engineering will be housed in the $30 million Bioengineering and Bioscience Building, which is under construction on Tech's campus and scheduled for completion in 1999.
For more information, you may contact Dr. Robert Nerem, Petit Institute for Bioengineering and Bioscience, Georgia Tech, Atlanta, GA, 30332-0363. (Telephone: 404/894-2768) (E-mail: email@example.com)
Emory/Tech partnership strengthens with biotech incubator.
The Georgia Institute of Technology and Emory University have formed a partnership to create a new center that could hatch some big business for the state of Georgia. It's an incubator for nurturing biotechnology companies.
Emory purchased the 42-acre Georgia Mental Health Institute complex on Briarcliff Road in Atlanta for $2.9 million and plans to convert much of the campus into an incubator for start-up biotechnology firms. The biotech industry includes companies that develop diagnostic procedures, medical devices and drugs.
The incubator concept draws on the success of Georgia Tech's Advanced Technology Development Center. The concept has the support of the Georgia Research Alliance and is a continuation of the partnership Tech has with Emory's research efforts.
"We think that this is an important expansion of the Emory/Georgia Tech collaboration," says Georgia Tech President Wayne Clough. "This is something that will substantially enhance the growing biotech movement in Atlanta. It will provide another piece to the foundation that will allow Atlanta to become one of the nation's premier biotechnology centers. The critical components for biotechnology success are research and space. This park, with the business incubator component, helps to satisfy both needs."
The concept of the biotechnology development center also takes full advantage of Georgia's biomedical resources, beginning with Emory and Georgia Tech, two of the fastest growing research institutions in the nation. Both have laboratories and scientists already producing technologies that are moving from the laboratory into production and patient care.
Journal of Technology
New scientific journal to post third edition on line.
The third issue of an on-line technical journal featuring the work of the Georgia Tech Research Institute (GTRI) will be posted on the World Wide Web in early February. The Journal of Technology, found at www.gtri.gatech.edu/jot/ targets scientists, engineers and research sponsors.
Articles in the third edition of the Journal of Technology include the following:
- "Pneumatic lift and control surface technology applied to high speed civil transport configurations," Robert J. Englar, Curt S. Niebur, Scot Gregory, Aerospace & Transportation Laboratory;
- "PC Based Tools for electronic combat systems," R. David Zobel, Jean Sands, Electronic Systems Laboratory;
- "Assessment of Scandium Additions to Aluminum Alloy Design," Henry G. Paris, T. H. Sanders, Y. Riddle, Electrooptics, Environment and Materials Laboratory, School of Materials Science and Engineering.
The Journal of Technology showcases the broad gamut of GTRI research, ranging from information technology to defense electronics and simulation to materials and manufacturing. The publication features both abstracts and full text of articles along with photographs, charts and illustrations. Authors' biographical information and e-mail addresses are provided along with links to the home pages of their respective laboratories.
The on-line publication, edited by GTRI researcher Henry Paris, is being updated quarterly.
For more information, contact Henry Paris, Electro-Optics, Environment and Materials Laboratory, Georgia Tech Research Institute, Atlanta, GA 30332-0826. (Telephone: 404/894-3688) (E-mail: firstname.lastname@example.org)
Water, Water Everywhere
Water Technology and Management Research Center established at Tech.
Researchers at the Georgia Institute of Technology and the French conglomerate Vivendi have begun a partnership to develop and demonstrate innovative technologies to improve the environmental and economic issues related to urban water and wastewater management.
photo by Stanley Leary Georgia Tech environmental engineering student Brian Skeens, left, and Dr. Appiah Amirtharajah, a professor in the School of Civil and Environmental Engineering, inspect water mixing equipment at the city of Atlanta's Water Pilot Plant. Amirtharajah and other Tech researchers are collaborating with scientists from Vivendi in a new endeavor called the Water Technology and Management Research Center.
The partnership created the Water Technology and Management Research Center in Atlanta last fall. The center serves as the North American node for Vivendi (formerly Compagnie Generale des Eaux) and is the second largest facility in the company's global research center network. Vivendi spends more than $40 million a year on water research.
The center draws upon the expertise of 11 faculty members and more than 100 graduate students in the Environmental Engineering Program of Tech's School of Civil and Environmental Engineering.
"One of the major factors that led to Vivendi's choice of Atlanta for establishment of the research center was the nationally recognized expertise of the faculty in the Environmental Engineering Group," says group leader and Tech professor Dr. Appiah (Amit) Amirtharajah. "They also were impressed with our state-of-the-art analytical capabilities, especially in drinking water treatment and wastewater management, developed with assistance from the Georgia Research Alliance.
"Also, Georgia Tech has a history of working with established companies to build research centers," Amirtharajah says.
He and his faculty are collaborating with Vivendi researchers in France, the United Kingdom, Denmark, Australia, Thailand, Malaysia and China. Vivendi has 210,000 employees worldwide and annual expenditures of $38 billion. Vivendi is the parent company of Air and Water Technologies and its engineering division, Metcalf and Eddy Inc.
Specific areas of research activity at the Tech center are:
- drinking water treatment and distribution;
- wastewater collection and treatment;
- wastewater reclamation and reuse;
- bio-solids management and disposal;
- and urban water management economics.
One example of collaboration between Tech and Vivendi researchers is a project headed by French researchers on static mixers for enhancement of drinking water ozonation. Tech researchers have been developing a computational fluid dynamics model of a static mixer and studying its use for mixing disinfectants to kill the parasite Cryptosporidium. The parasite has caused major waterborne disease outbreaks in Carrollton, Ga., Milwaukee, Wis., London, England, and Sydney, Australia.
The research center is linking these ongoing research activities and assisting in global technology transfer of these innovations for supplying safe drinking water. For now, the center is housed in the School of Civil and Environmental Engineering. Within a few years, Vivendi expects to have 50 researchers at the Tech center and coordinate research of $8 million to $9 million a year.
Jane M. Sanders
For more information, you may contact Dr. Appiah (Amit) Amirtharajah, School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0512. (Telephone: 404/894-0628) (E-mail: email@example.com)
A single algorithm unlocks several problems.
Creating a stir in ciphering circles, a Georgia Institute of Technology math professor and his collaborators have solved the even directed cycle problem an algorithmic enigma that has kept graph theorists and computer scientists scratching their heads for some 25 years.
photo by Stanley Leary Dr. Robin Thomas, right, a Georgia Institute of Technology math professor, has solved the even directed cycle problem an algorithmic enigma that has kept graph theorists and computer scientists scratching their heads for some 25 years. Student Christopher Carl Heckman, left, has helped implement the algorithm.
In simple terms, a cycle is similar to a tour of one-way streets, returning to the starting point without passing through any intersection or street more than once. Thus, an even cycle means travelling down an even number of streets without repetition a problem of great interest to computer scientists for modeling purposes. Deceptively complex, the problem may have been easy enough to state, but remained difficult to resolve.
Two years ago, Georgia Tech's Dr. Robin Thomas, along with Dr. Neil Robertson, a math professor at Ohio State University, and Dr. P.D. Seymour, a math professor at Princeton University, spent the summer at Princeton scrutinizing the decades-old problem. Their powwow produced a proof, which they then simplified over the next year. During the refinement process, the trio was able to design an efficient algorithm (one that tackles a complex system of streets and produces the answer in real time) for determining whether an even-directed cycle exists.
What's more, this algorithm can be applied to several other situations. "There are about six problems, that sound different at first, but over the years have proven to be equivalent. So, if you solve one of them, you can solve all of them," Thomas explains.
Economics The new algorithm sheds light on economic relationships. Consider a model of a banana trade with four economic quantities: the supply of bananas, the demand for bananas, the price of a banana and people's taste for bananas.
"Now simple economic principles tell us that as the price of bananas increases, so does the supply (farmers will produce more bananas), and the demand decreases (people will buy fewer bananas)," Thomas says. "And, for a fixed price, as people's taste for bananas increases, so does their demand for bananas. From these observations it is possible to mathematically prove that as people's taste for bananas increases, so do the price and demand.
"Thus we deduce something about qualitative relationships of the quantities without knowing their actual values," Thomas says. "To decide in general (when you have hundreds or thousands of such quantities) what relationships exist is equivalent to the even cycle problem, and hence can be solved by our algorithm."
Statistical mechanics Atoms often bond with each other, and physicists are interested in calculating the so-called "entropy," which measures the capacity of a system to undergo change. One method, developed in the 1960s, works for planar lattices, but it was not known how far this method could go. "With our algorithm, we provide a way to determine precisely for which structures this method works, and when it works we have a tool for calculating the entropy," Thomas explains.
Permanents This is related to the concept of determinant of a matrix, which is a common engineering tool. The permanent is very similar, but much harder to compute. The new proof makes it possible to decide when a permanent of a matrix can be calculated by reducing it to a determinant of a related matrix, answering a question posed by mathematician George Polya in 1913. Even though the permanent can't be calculated efficiently in every case, it widens the scope.
An extended abstract of "Permanents, Pfaffian Orientations and Even Directed Circuits," was presented at the Symposium on the Theory of Computing in 1997, and the complete paper was recently accepted for publication in the Annals of Mathematics.
Two of Thomas' students, Christopher Carl Heckman and Petr Hlineny, have implemented the algorithm and made it available interactively on the World Wide Web. Interested researchers can point their browsers to http://math36.math.gatech.edu:8080/evenc.html.
For more information, you may contact Dr. Robin Thomas, School of Mathematics, Georgia Institute of Technology, Atlanta, GA, 30332-0160. (Telephone: 404/894-2733) (E-mail: firstname.lastname@example.org)
Protecting the Beat of Life
Test center studies interaction between pacemakers and electronic article surveillance systems.
As electronic components become smaller and smarter, they allow development of increasingly sophisticated pacemakers, implantable defibrillators and other medical devices that have improved life for more than a million people worldwide. At the same time, growing concern about theft from retail stores has led to widespread use of electronic article surveillance (EAS) systems that generate fields of electromagnetic energy while in operation.
photo by Stanley Leary GTRI senior research engineer Jimmy A. Woody tests a pacemaker at the EAS/Medical Device E3 Test Center. Concern exists that such devices can malfunction when they encounter fields of electromagnetic energy generated by electronic article surveillance (EAS) systems in retail stores.
Those electromagnetic fields can potentially interfere with operation of sensitive medical devices, causing concern for some store customers using pacemakers or implantable defibrillators.
Researchers at the Georgia Tech Research Institute (GTRI) are working with manufacturers of both types of equipment to understand, and therefore help prevent, potentially harmful interactions. The work takes place at the EAS/Medical Device E3 Test Center, a unique facility supported by manufacturers of the electronic article surveillance systems.
"As both groups of manufacturers learn more about one another, there will be fewer and fewer potential interactions," says GTRI senior research engineer Jimmy A. Woody, manager of the test center. "What's unique here is that the manufacturers of the energy source and the manufacturers of the medical devices are cooperating to set up and use a test center that benefits both groups."
Support to set up the test center came from the International Electronic Article Surveillance Manufacturers Association, which estimates that 400,000 EAS systems are used worldwide. Typically placed near store exits and entrances, the EAS systems use electromagnetic energy to detect special tags placed on items stores wish to protect.
In the test center, Woody and research engineer Ralph M. Herkert subject pacemakers, defibrillators and other devices to the energy fields created by a representative sample of eight EAS systems and two EAS system tag deactivators provided by their manufacturers. Using standardized test procedures, they measure how the medical devices respond through their full range of operation.
The resulting data is used by the manufacturers' design and quality assurance departments to improve their products, if necessary. Thus, this data helps the manufacturers ensure that interference, which could harm wearers of medical devices, does not occur.
Testing takes place with the devices submerged in a tank of saline solution that simulates the electromagnetic behavior of the human torso. Using a computer-controlled positioner, the tank containing the medical device is moved through each merchandise control system in a manner that simulates the way customers might walk through such systems in retail stores. The test protocol also simulates customers standing in a checkout line near equipment used to deactivate the control tags.
Because of a non-disclosure agreement, Woody and Herkert provide the data they generate only to the manufacturers who submit the devices. The researchers do not have medical training, so they do not render judgments about the health implications of the data they measure.
But Woody says the medical devices are carefully designed to handle interference. So when the researchers do measure a response to any electromagnetic field, it tends to be subtle such as temporary changes in pulse rates and missed beats. And the devices recover quickly.
For the full text news release, see www.gtri.gatech.edu/res-news/E3TEST.html. For more information, you may contact Jimmy Woody, Sensors & Electromagnetic Applications Lab, Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, GA 30332-0822. (Telephone: 404/894-8326) (E-mail: email@example.com); or Ralph Herkert, Sensors & Electromagnetic Applications Lab, Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, GA 30332-0822. (Telephone: 404/894-8602) (E-mail: firstname.lastname@example.org).
Faculty/Staff Honors and Awards
Joseph Bruder, a principal research engineer at the Georgia Tech Research Institute, was elected a fellow of the Institute of Electrical and Electronics Engineers (IEEE). Only about 1 percent of IEEE's 300,000 members have earned the fellow designation.
J.G. "Jim" Dai, an applied probabilist with joint appointments in the School of Mathematics and the School of Industrial and Systems Engineering, received the Erlang Prize for his outstanding contributions to the field of applied probability. Sponsored by the Section on Applied Probability of the Institute for Operations Research and the Management Sciences, the Erlang Prize is the most prestigious award for young applied probabilists.
Patricia Dove, an associate professor in the School of Earth and Atmospheric Sciences, and graduate student H. Henry Teng won the Mineralogical Society of America's Best Paper Award. Their paper titled "Surface Site-Specific Interactions of Aspartate with Calcite: Implications for Biomineralization" appeared in the 1997 American Mineralogist (Vol. 82, p. 878-887).
Rosario A. Gerhardt, an associate professor in the School of Materials Science and Engineering, was inducted as a fellow of the American Ceramic Society (ACeRS). Only 26 members were elected fellows in 1998. Gerhardt also is the new program chair of the electronics division of ACeRS.
M. Jackson Marr, a professor and experimental psychologist in the School of Psychology, was elected president of the Division of Experimental Analysis of Behavior of the American Psychological Association. Marr's recent research activities address the development and assessment of precision learning techniques and other instructional systems for teaching engineering physics. He also studies the applications of dynamical systems theory to operant conditioning, applications of behavior analysis at Zoo Atlanta and theoretical issues in behavioral analysis.
Robert Michelson, a principal research engineer at the Georgia Tech Research Institute, won the 1998 Pioneer Award presented by the Association for Unmanned Vehicle Systems International. The award is the highest recognition in the unmanned systems industry for technical contributions that advance the state-of-the-art, while moving the community toward the new millennium. The 1997 winner was former U.S. Secretary of Defense William J. Perry.
Ward O. Winer, Regents' professor and chair of the School of Mechanical Engineering, received the 1998 University of Michigan Alumni Society Merit Award from the Department of Mechanical Engineering and Applied Mechanics.
Jan Youtie, a senior research associate at the Economic Development Institute, and Phil Shapira, an associate professor in the School of Public Policy, won a Lang Rosen "Gold Award" for their article, "Tracking Customer Progress: A Follow-up Study of Customers of the Georgia Manufacturing Extension Alliance." They received a similar award in 1997 for "Coordinating Manufacturing Extension Services: Impacts and Insights from the U.S. Manufacturing Extension Partnership." The awards, given annually by the Technology Transfer Society, recognize excellence in content and writing.
Last updated: October 7, 1998
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