OREGON STATE UNIVERSITY

college of engineering

“Negative refraction” opens avenue to new products and industries

CORVALLIS, Ore. – Researchers at Oregon State University have discovered a way to make a low-cost material that might accomplish negative refraction of light and other radiation – a goal first theorized in 1861 by a giant of science, Scottish physicist James Maxwell, that has still eluded wide practical use.

Other materials can do this but they are based on costly, complex crystalline materials. A low-cost way that yields the same result will have extraordinary possibilities, experts say – ranging from a “super lens” to energy harvesting, machine vision or “stealth” coatings for seeming invisibility.

Entire new products and industries could be possible. The findings have just been published and a patent has been applied for on the technology.

The new approach uses ultra-thin, ultra-smooth, all-amorphous laminates, essentially a layered glass that has no crystal structure. It is, the researchers say, a “very high-tech sandwich.”

The goal is to make radiation bend opposite to the way it does when passing through any naturally occurring material. This is possible in theory, as Maxwell penciled out during the American Civil War. In reality, it’s been pretty difficult to do.

“To accomplish the task of negative refraction, these metamaterials have to be absolutely perfect, just flawless,” said Bill Cowell, a doctoral candidate in the OSU School of Electrical Engineering and Computer Science. “Everyone thought the only way to do that was with perfectly crystalline materials, which are quite expensive to produce and aren’t very practical for large-area commercial application.

“We now know these materials may not need to be that exotic.”

The new study has explained how easy-to-produce laminate materials, created with technology similar to that used to produce a flat panel television, should work for this purpose. The findings outline the component materials and the theoretical behavior of the laminates, Cowell said. They were just published in Physica Status Solidi A, in work supported by the National Science Foundation.

“We haven’t yet used this approach to achieve negative refraction, but the findings suggest it should work for that,” he said. “That will be one goal of continuing research. No one had thought of using amorphous metals for this purpose. They didn’t think it could be that simple.”

Negative refraction, Cowell said, is a brilliant idea. It is based on the equations developed by the young physicist and mathematician Maxwell more than 150 years ago – work for which he is revered, along with Isaac Newton and Albert Einstein, as one of the greatest physicists who ever lived. Einstein kept a photograph of Maxwell on his office wall.

But for generations, theory is about all that it was. Just in the past decade have researchers finally figured out how to create materials of any type that can achieve negative refraction. A way to accomplish that at low cost for the commercial marketplace could be of considerable importance, scientists say.

One application of particular interest is a “super lens,” a device that might provide light magnification at levels that dwarf any existing technology. Many applications are possible in electronics manufacturing, lithography, biomedicine, insulating coatings, heat transfer, space applications, and perhaps new approaches to optical computing and energy harvesting.

The discovery of amorphous metamaterials is an outgrowth of recent findings at OSU about ways to create a metal-insulator-metal, or MIM diode, also of commercial significance. The OSU research is one of the latest advances in “dispersion engineering,” or the control of electromagnetic radiation.

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William Cowell, 541-758-2895

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Negative refraction

For disaster debris arriving from Japan, radiation least of the concerns

CORVALLIS, Ore. – The first anniversary is approaching of the March, 2011, earthquake and tsunami that devastated Fukushima, Japan, and later this year debris from that event should begin to wash up on U.S. shores – and one question many have asked is whether that will pose a radiation risk.

The simple answer is, no.

Nuclear radiation health experts from Oregon State University who have researched this issue following the meltdown of the Fukushima Dai-ichi nuclear plant say the minor amounts of deposition on the debris field scattered in the ocean will have long since dissipated, decayed or been washed away by months of pounding in ocean waves.

However, that’s not to say that all of the debris that reaches Pacific Coast shores in the United States and Canada will be harmless.

“The tsunami impacted several industrial areas and no doubt swept out to sea many things like bottled chemicals or other compounds that could be toxic,” said Kathryn Higley, professor and head of the Department of Nuclear Engineering and Radiation Health Physics at OSU.

“If you see something on the beach that looks like it may have come from this accident, you shouldn’t assume that it’s safe,” Higley said. “People should treat these debris with common sense; there could be some things mixed in there that are dangerous. But it will have nothing to do with radioactive contamination.”

Higley and other OSU experts have been active in studying the Fukushima accident since it occurred, and are now doing research to help scientists in Japan better understand such issues as uptake of radioactive contamination by plants growing near the site of the accident. They also studied marine and fishery impacts near Japan soon after the incident.

“In the city and fields near Fukushima, there are still areas with substantial contamination, and it may be a few years before all of this is dealt with,” Higley said. “But researchers from all over the world are contributing information on innovative ways to help this area recover, including some lessons learned from the much more serious Chernobyl accident in 1986 in the Ukraine.”

Some of the technology to deal with this is complex. Other approaches, she said, can be fairly low-tech – removal of leaf litter, washing, plowing the ground, collecting and concentrating water runoff.

The repercussions of the event in the ocean, however, and implications for distant shores are much more subdued. Most of the discharge that was of concern was radionuclides of iodine and cesium, which were deposited on widely dispersed, floating marine debris days after the tsunami. Most of the iodine by now will have disappeared due to radioactive decay, and the cesium washed off and diluted in the ocean.

“There are a lot of misconceptions about radioactivity,” Higley said. “Many people believe that if it can be measured, it’s harmful. But we live in a world of radiation coming to us from the sun, or naturally present in the earth, or even from our own bodies.

“There are higher natural levels of radiation found all around the Rocky Mountains, for instance,” she said. “And we can still measure radioactive contaminants in nature from old atmospheric nuclear weapons tests more than 50 years ago.”

Like most of those other forms of radiation, Higley said, any measurable radioactivity found on debris from Fukushima should be at very low levels and of no health concern – much less, for instance, than a person might receive in a single X-ray.

Debris from Japan should start to arrive in the U.S. and Canada late this year or in 2013 following normal ocean currents, say other OSU experts who are studying this issue. When they do, some aspects of them might be dangerous – a half-filled, floating, sealed bottle of a toxic chemical, for instance. So people should exercise caution.

But they don’t need to worry about radiation.

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Kathryn Higley, 541-737-0675

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Radiation uptake

Kathryn Higley

Aftershocks of Japan disaster being felt in U.S. earthquake planning

CORVALLIS, Ore. – The repercussions of last year’s subduction zone earthquake and tsunami in Japan are now being felt in the Pacific Northwest, as experts and disaster managers better understand the enormous risks facing this region, plan for the challenges ahead and prioritize the most urgent needs.

Before the event, scientists knew that similar concerns faced Oregon, Washington, northern California and British Columbia from the Cascadia Subduction Zone. But they have now seen how such long-lasting events produce soil “liquefaction” far worse than expected, the potential for devastated roads and bridges, a collapsed infrastructure and even threats to their economic future.

“Just in Oregon we’ve got a billion dollar problem, but we don’t have a billion dollars,” said Scott Ashford, professor and interim dean of the College of Engineering at Oregon State University, and one of the international engineering experts who toured the affected area in Japan last year shortly after the disaster.

“The challenge for Oregon and our neighboring states is to prioritize the concerns, and figure out some way to preserve the most critical lifelines – key roads, airports, port facilities and utility networks,” Ashford said. “In Japan, nearly 30,000 people died, many in the days after the disaster because no one could reach them. We don’t want that to happen here, and we don’t want our economy to collapse.”

The Japanese event has galvanized some action, Ashford said, but much more remains to be done. It prompted the legislature to call for an Oregon Resilience Plan that will explore many of these issues – an emergency transportation plan, needed seismic upgrades, ways to protect life and public safety and allow a shattered region to rebuild.

OSU is working closely with the Oregon Department of Transportation and other state agencies to assist with these efforts, and also just joined the Pacific Earthquake Engineering Research Center, an initiative to collaborate with all of the leading academic institutions in this field on the West Coast.

One of the primary lessons from Japan, Ashford says, is the enormous damage done by liquefaction - a continued shaking of the ground that turns soils into mush. In events such as this, it is amplified by the sheer length of the event, an earthquake that can shake not just for 30 seconds but up to five minutes.

Many of the soils in Portland, Ore., parts of the Willamette Valley and other areas of Oregon, Washington and California are particularly vulnerable to this phenomenon, Ashford said, which can magnify the distance and extent of damage.

“In Japan, entire structures were tilting and sinking into the sediments, even while they remained intact,” Ashford said. “The shifts in soil destroyed water, sewer and gas pipelines, crippling the utilities and infrastructure these communities need to function. We saw some places that sank as much as four feet.”

The data provided by analyzing the Japanese earthquake is now being used by OSU and others to improve understanding of this soil phenomenon and better prepare for it. Future construction in some places may make more use of techniques known to reduce liquefaction, such as better compaction to make soils dense, or use of reinforcing stone columns.

Many areas from northern California to British Columbia have younger soils vulnerable to liquefaction - on the coast, near river deposits or in areas with filled ground. The “young” sediments, in geologic terms, may be those deposited within the past 10,000 years or more. In Oregon, for instance, that describes much of downtown Portland, the Portland International Airport, nearby industrial facilities and other cities and parts of the Willamette Valley.

The Oregon Department of Transportation has concluded that 1,100 bridges in Oregon are at risk, and fewer than 15 percent of them have been retrofitted to prevent collapse. Lateral movement is also a concern.

“Buildings that are built on soils vulnerable to liquefaction not only tend to sink or tilt during an earthquake, but slide downhill if there’s any slope, like toward a nearby river,” Ashford said. “This is called lateral spreading. In Portland we might expect this sideways sliding of more than four feet in some cases, more than enough to tear apart buildings and buried pipelines.”

Japan had excellent building codes, researchers say, and was far better prepared for this type of earthquake than the U.S. will be. Much of the “legacy” infrastructure in the Pacific Northwest was built before these risks were known.

“The disaster in Japan just clarifies what we need to do,” Ashford said. “And it’s not something we can do in a year or two, but something that will take a decade or two. At stake are the lives of our people and the future of our economy, and that’s something that should matter to every individual.”

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Scott Ashford, 541-737-5232

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Sinking building


Settlement caused by liquefaction

Liquefaction


Video of the liquefaction

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Researchers eye monitoring system for offshore wind energy impacts

CORVALLIS, Ore. – The next generation of wind energy facilities in the United States may be built offshore where winds are stronger, floating platforms could be utilized, and links to power grids may already exist.

Though the development of such offshore wind towers locally is still in the conceptual stage, there already is concern over the potential impacts that the huge, rotating blades of wind turbines could have on seabirds and bats. Even attempting to monitor such impacts is daunting.

The Northwest National Marine Renewable Energy Center at Oregon State University has received a three-year, $600,000 grant from the U.S. Department of Energy to develop a multi-sensor array to record the interactions – including impacts – of birds and bats on the blades, platforms and towers of wind turbines.

“Unfortunately, the usual way to document the impact of wind turbines on birds and bats is to collect the carcasses,” said Robert Suryan, an OSU seabird expert who is principal investigator on the project. “That would be hard to do out in the ocean. Even on shore, surveys are limited at large or remote facilities and can be compromised by scavengers that remove the carcasses.”

So the researchers are coming up with a different approach – synchronizing an array of sensors that will include accelerometers to measure variations in blade movement from impact, visual and infrared cameras, and acoustic devices to record strikes and identify the bird or bat involved. The monitoring system will be designed to run continuously and on multiple turbines at once to estimate the potential impact of the entire wind farm.

The project team led by Suryan includes co-principal investigators Roberto Albertani, an OSU engineer, and Brian Polagye, an engineer from the University of Washington.

“This is the first foray into offshore wind energy for the Northwest National Marine Renewable Energy Center,” said Belinda Batten, who directs the center, which is a joint effort between OSU and the University of Washington. “It builds upon our strengths in wave and tidal energy, and our efforts to gauge potential environmental impacts of new forms of renewable energy.”

Though the researchers’ focus will be on an array for offshore turbines, the sensors will have potential usage in terrestrial facilities as well, pointed out Suryan, an assistant professor of fisheries and wildlife at OSU, who works at the university’s Hatfield Marine Science Center in Newport.

The technologies for the array are not new, the researchers say, but integrating the instruments and developing automated strike detection software to capture events – and then remotely transmit relevant data – has not been done. In addition to the engineering challenge, the researchers must account for the impact of the rugged Pacific Ocean, where winter storms frequently produce 20- and 30-foot waves.

“In Oregon, many seabirds are heavy-bodied and fly close to the surface of the ocean – possibly below the sweep of the rotor blades,” Suryan said. “Potential collision with the lower tower and base is still a concern and will be monitored by this system. Studies are needed to identify which species fly at altitudes that might put them at risk of blade impact; we know less about how far and frequently bats move offshore.

“There is also the issue with platforms, which might attract birds as a roosting area,” Suryan added. “Some of it may depend on how far offshore they might be.”

The researchers will spend much of the next three years developing their instrumentation array and synchronizing the instruments. They will test their instrument array on land in Newport and on experimental turbines at Mesalands Community College in New Mexico and the National Renewable Energy Laboratory in Colorado.

“There is a big push in New England to develop offshore wind energy, as well as in areas where oil and gas platforms already exist,” Suryan said. “One possibility is to use those platforms for hydroelectric power generation from the currents below, and wind energy from turbines above the surface. Our project was funded from an initiative to remove market barriers for developing offshore wind facilities, especially floating platforms that can be used in deep water.

“Regardless of where wind energy platforms are built – on land, or at sea – placement is critical,” he added. “You want to avoid major flyways and travel corridors.”

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Rob Suryan, 541-867-0223

Oregon preparing for debris from Japanese tsunami

CORVALLIS, Ore. – As the one-year anniversary of the devastating March 11, 2011, Japanese earthquake approaches, and debris from the ensuing tsunami moves closer to the West Coast, a group of Oregon agencies, university scientists, political staff, non-governmental organizations and others is preparing for its arrival.

This week, the group held a conference call to review Oregon’s response to the potential arrival of the debris and to chart a communication strategy to educate West Coast residents about what may happen. Questions directed at state and county leaders, Oregon State University Extension experts, the OSU Hatfield Marine Science Center and others are increasing daily.

When will the debris arrive? Where will it land? Is there any danger of radioactivity? What shall we do if we find something?

Jack Barth, an OSU oceanographer and expert in ocean currents, said the debris is still months away from arriving on the West Coast, though it is possible that strong winds may push some floating items that rise high above the surface more quickly to the North American shore. Floats from Japanese fishing nets have washed up on the Washington coast in recent weeks, but those haven’t been tied directly to the tsunami.

“Material from Asia washes up on the West Coast routinely,” Barth said. “It doesn’t necessarily mean it is tsunami-related. A Russian ship discovered a small Japanese fishing boat in the waters north of Hawaii in October that was definitively tied to the tsunami – and it was about where we thought it should be, given the currents.” NOAA reports no radiation was detected on the fishing boat.

Barth, who is the associate dean of OSU’s College of Earth, Ocean, and Atmospheric Sciences, has met with U.S. Sen. Ron Wyden, and representatives of the National Oceanic and Atmospheric Administration (NOAA) and various Oregon agencies and organizations in recent weeks. He said it is difficult to calculate how much debris remains in the ocean, and what exactly will arrive on our shore.

When and how it arrives is a matter of ocean physics, he pointed out.

“Much of the debris generated from the earthquake and tsunami has or will become waterlogged, weighed down with barnacles or other organisms, and sink,” Barth said. “A large fraction of it will be diverted south into the ‘Garbage Patch’ between Hawaii and the West Coast, and may circulate in that gyre.

“What remains should arrive here at the end of 2012, or the beginning of 2013,” he added. “If it arrives in the fall and winter, it will get pushed up north by the currents to Washington, British Columbia and even Alaska. Debris arriving in late spring and summer will hit Oregon and be swept south into California waters.”

What does arrive is unlikely to be dangerous, according to Kathryn Higley, professor and head of the Department of Nuclear Engineering and Radiation Health Physics at OSU. Higley was one of the most widely cited scientists following the incidents at Japan’s Dai-ichi nuclear plant after the earthquake. She says the lag time between the tsunami and the nuclear incident, coupled with the vastness of the ocean, makes it unlikely that the debris will carry any danger from radiation.

“The major air and water discharges of radioactive material from the Dai-ichi plants occurred a few days after the debris field was created by the tsunami,” Higley pointed out. “So the debris field was spread out at the time the discharges occurred. This would have diluted the radiological impact.

“Secondly, wind, rain and salt spray have been pummeling this material for months,” she said. “The key radionuclides are composed of iodine and cesium – which are chemically a lot like chlorine and sodium. Most of the iodine has gone because of radioactive decay. The radioactive cesium, to a great extent, will be washed off and diluted in the surrounding ocean.

“Therefore, while we may be able to detect trace amounts of radioactive material on this debris, it’s really unlikely that there will be any substantial radiation risk,” Higley said.

Staci Simonich, an OSU professor of Environmental and Molecular Toxicology, has been monitoring the air for emissions from Japan and said that since last April (2011), radiation levels were at “background.”

“Those are naturally occurring levels – at concentrations far below standards for public safety,” she said.

NOAA is monitoring the debris from a national perspective and has a website that can educate the public and keep interested persons updated. It is at http://marinedebris.noaa.gov/.  The agency suggests that beachcombers and others who find material they think may be from Japan report it at disasterdebris@noaa.gov – and use common sense.

They write: “As with any outdoors activity, it is important to follow common sense and put safety first. Avoid picking up debris that you are not well-equipped and trained to handle. For example, be careful of sharp objects that could cut yours hands; avoid picking up sealed containers of chemicals – they may crack or break and spill the content on you; likewise, report any full drum on the beach, and avoid handling it yourself. If you are uncomfortable handling any debris item, leave it where it is.”

Jamie Doyle, an OSU Extension Sea Grant specialist in Coos and Curry counties, said a variety of Oregon agencies and non-governmental organizations are beginning to plan for various response scenarios. As Oregon’s planning progresses, she says, “expect more information for the public.”

“One other concern is what should happen if someone finds any personal effects,” Doyle said. “A lot of people lost their lives, and many people still have family members who are missing. We need to be sensitive to the possibility of finding something that may be of personal significance to someone in Japan.”

Tomoko Dodo, from the Consulate General of Japan’s office in Seattle, has asked that persons finding something that could be considered a personal “keepsake” for a survivor report it to local authorities, or the consulate in Seattle at 206-682-9107.

Patrick Corcoran, an OSU Extension Sea Grant specialist for the North Coast, said the focus thus far has been on research and “building the capacity to respond” to the arrival of the debris. Specific information on Oregon resources and contacts will be forthcoming, he said.

Among the other organizations working on planning Oregon Surfrider Foundation, Stop Oregon Litter and Vandalism (SOLV), Coast Watch, Oregon Emergency Management, Oregon Public Health Division; West Coast Governors’ Alliance; Oregon Parks and Recreation Department;  Oregon Refuse and Recycling Association; Oregon Fishermen’s Cable Committee; Office of U.S. Sen. Ron Wyden; Office of Oregon Gov. John Kitzhaber; Washed Ashore; Oregon Department of Environmental Quality; Oregon Department of Land Conservation and Development; U.S. Coast Guard; and Western Oregon Waste.

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Jack Barth, 541-737-1607

“Life and activity monitor” provides portable recording of vital signs

The study this story is based on is available in ScholarsArchive@OSU: http://bit.ly/x2EjDF

CORVALLIS, Ore. – Researchers have developed a type of wearable, non-invasive electronic device that can monitor vital signs such as heart rate and respiration at the same time it records a person’s activity level, opening new opportunities for biomedical research, diagnostics and patient care.

The device is just two inches wide, comfortable, does not have to be in direct contact with the skin and can operate for a week without needing to be recharged. Data can then be downloaded and assessed for whatever medical or research need is being addressed.

The technology has been reported at a professional conference, and research is continuing to make it even smaller and less costly.

“When this technology becomes more miniaturized and so low-cost that it could almost be disposable, it will see more widespread adoption,” said Patrick Chiang, an assistant professor of computer engineering at Oregon State University. “It’s already been used in one clinical research study on the effects of micronutrients on aging, and monitoring of this type should have an important future role in medicine.”

Called a “life and activity monitor,” the system uses different sensors to detect heart rate, respiration, movement and similar vital signs. It will provide doctors, researchers and clinicians a continuous flow of data over time, reduce the need for more frequent office visits, and ultimately provide better care at lower cost.

The system was developed by scientists and engineers at Oregon State University and the University of California at San Diego.

Final designs of the technology may be as small as a disposable bandage, researchers say.

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Patrick Chiang, 541-737-5551

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Conference to explore progress toward safer fuel in nuclear research reactors

CORVALLIS, Ore. – A group of national experts on an initiative to use fuel that is less-highly enriched in nuclear research and test reactors will meet Jan. 10-11 at Oregon State University, to explore recent progress toward this goal and work still to be done.

Members of this High Performance Research Reactor Working Group are part of a program that began more than 30 years ago, and has recently accelerated its efforts in the interest of enhanced nuclear security.

There are only five civilian research and test reactors in the United States that now use highly enriched uranium for their operation, out of the original 47 in 1978. Research and test reactors in the U.S. have never used material that could be used in the production of large-scale nuclear weapons, but there has always been concern about the potential for these radioactive materials to be used in “dirty bombs.”

“This is the last stretch in this program,” said Wade Marcum, an OSU assistant professor of nuclear engineering. “Ultimately we plan to convert all civilian research and test reactors to using low-enriched fuels, but the remaining reactors using high-enriched fuels require very specific fuel designs in order to conduct their ongoing research.”

It’s a difficult engineering task, experts say, to design a new type of low-enriched uranium fuel that still allows each reactor to maintain its current research capabilities. Several viable fuel designs have been identified and are in the process of being implemented in each reactor.

OSU converted its research reactor to low-enriched fuel several years ago, and is playing a key role in these efforts. It has a multi-million dollar contract from the Idaho National Laboratory to help test and study new types of fuels that have a lower level of enrichment but still offer the performance needed.

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Wade Marcum, 541-737-3018

OSU engineering student recognized as one of top 15 in the world

CORVALLIS, Ore. – Alexandria Moseley, an engineering student at Oregon State University, has been named one of the 15 most promising college engineering students in the world as part of National Engineers Week.

Moseley, from Newberg, Ore., is a senior in the School of Mechanical, Industrial and Manufacturing Engineering at OSU, and was nominated for this “New Faces of Engineering” honor by the SME Education Foundation, which has provided her with scholarship support.

“The further I delve into my industrial and manufacturing engineering studies, the more aware I become of just how largely our society depends on this area of work,” Moseley said. “The opportunity to positively influence the field of manufacturing, whether by instruction or research, provides all the challenge and personal fulfillment I could ever desire in a career.”

Moseley has participated in several internships and projects while at OSU, served as a College of Engineering Ambassador, and been active in outreach programs to alumni, industry, prospective students and others.

This is the first year that National Engineers Week has recognized college engineering students. Winners were cited for their academic excellence, leadership in student organizations, community service and other activities.

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Bart Aslin, 313-425-3300

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Alexandria Moseley

“Fool’s gold” leads to new options for cheap solar energy

CORVALLIS, Ore. – Pyrite, better known as “fool’s gold,” was familiar to the ancient Romans and has fooled prospectors for centuries – but has now helped researchers at Oregon State University discover related compounds that offer new, cheap and promising options for solar energy.

These new compounds, unlike some solar cell materials made from rare, expensive or toxic elements, would be benign and could be processed from some of the most abundant elements on Earth. Findings on them have been published in Advanced Energy Materials, a professional journal.

Iron pyrite itself has little value as a future solar energy compound, the scientists say, just as the brassy, yellow-toned mineral holds no value compared to the precious metal it resembles. But for more than 25 years it was known to have some desirable qualities that made it of interest for solar energy, and that spurred the recent research.

The results have been anything but foolish.

“We’ve known for a long time that pyrite was interesting for its solar properties, but that it didn’t actually work,” said Douglas Keszler, a distinguished professor of chemistry at OSU. “We didn’t really know why, so we decided to take another look at it. In this process we’ve discovered some different materials that are similar to pyrite, with most of the advantages but none of the problems.

“There’s still work to do in integrating these materials into actual solar cells,” Keszler said. “But fundamentally, it’s very promising. This is a completely new insight we got from studying fool’s gold.”

Pyrite was of interest early in the solar energy era because it had an enormous capacity to absorb solar energy, was abundant, and could be used in layers 2,000 times thinner than some of its competitors, such as silicon. However, it didn’t effectively convert the solar energy into electricity.

In the new study, the researchers found out why. In the process of creating solar cells, which takes a substantial amount of heat, pyrite starts to decompose and forms products that prevent the creation of electricity.

Based on their new understanding of exactly what the problem was, the research team then sought and found compounds that had the same capabilities of pyrite but didn’t decompose. One of them was iron silicon sulfide.

“Iron is about the cheapest element in the world to extract from nature, silicon is second, and sulfur is virtually free,” Keszler said. “These compounds would be stable, safe, and would not decompose. There’s nothing here that looks like a show-stopper in the creation of a new class of solar energy materials.”

Work to continue the development of the materials and find even better ones in the same class will continue at the National Renewable Energy Laboratory in Colorado, which collaborated on this research.

The work was done at the Center for Inverse Design, a collaborative initiative of the College of Science and College of Engineering at OSU, formed two years ago with a $3 million grant from the U.S. Department of Energy. It was one of the new Energy Frontier Research Centers set up through a national, $777 million federal program to identify energy solutions for the future.

The OSU program is different from traditional science, in which the process often is to discover something and then look for a possible application. In this center, researchers start with an idea of what they want and then try to find the kind of materials, atomic structure or even construction methods it would take to achieve it.

Finding cheap, environmentally benign and more efficient materials for solar energy is necessary for the future growth of the industry, researchers said.

“The beauty of a material such as this is that it is abundant, would not cost much and might be able to produce high-efficiency solar cells,” Keszler said. “That’s just what we need for more broad use of solar energy.”

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Douglas Keszler, 541-737-6736

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Pyrite

Pyrite, or "fools gold"

Unseen devastation from tsunamis can destroy coral reefs

CORVALLIS, Ore. – The large tsunami two years ago in American Samoa has given scientists a chance to examine an issue that often seems of little significance in the immediate aftermath of these massive disasters – the little-seen, rarely studied but often frightening damage done to offshore coral reefs.

A new study by scientists from Oregon and Michigan, done with a remotely operated undersea vehicle, or ROV, surveyed large areas of that area’s coral reefs, and revealed significant damage from sediment, debris, and the enormous forces of both the incoming and outgoing waves.

Corals are delicate living organisms that can only survive in shallow, nearshore areas where they get adequate sunlight. That’s also where the tsunami wave action is most violent, and they are especially vulnerable to its impacts – but often ignored in the understandable concern about terrestrial damage and loss of life.

“Very little until now has been known about the impact of tsunamis on coral reefs,” said Solomon Yim, a professor of structural and ocean engineering at Oregon State University and co-author of the study, which was supported by the National Science Foundation.

“These are huge forces and often these events have happened in remote locations of the world where we had little opportunity to study them,” Yim said. “American Samoa gave us the chance to use some very sophisticated equipment to gain a much better understanding of what damage is being done to coral reefs, and what might be done in the future to help reduce it.”

On Sept. 29, 2009, a magnitude 8.3 subduction zone earthquake near American Samoa sent waves crashing into many islands, destroying buildings and eroding coastlines with waves up to 20 feet high that came almost a mile inland and killed more than 180 people. It was the world’s largest earthquake that year.

The onshore devastation was heavy. Although not seen at the time, so was the underwater damage to coral reefs.

“We found tires, clothing, sheet metal roofs, and window frames littered on the reefs,” Yim said. “Much of the coral was broken or covered with sediments, and some of it died as a result. Both the run-up and run-down of the tsunami waves were very destructive. It will probably take years to decades for the reef to recover.”

The sediments and debris carried by the rapid drawdown back into the sea can be harmful to the delicate marine ecosystem, the researchers noted in their report. They introduce bacteria and toxic chemicals, erode the seafloor and destroy the reef.

Work with the ROV examined the reefs five weeks after the tsunami, when they were still deeply scarred. Some corals were ripped up and tossed onshore, others broken and sucked back into deep water. In either case they would not survive. Hours of video footage were made of the damage, and the research indicated the drawdown of the water was even more destructive than the incoming waves.

Most of the damage and debris was found in comparatively shallow ocean waters, about 30 to 70 feet deep.

Since so little is known about the damage to coral reefs by tsunamis, more studies are needed to examine the influence of water depth, three-dimensional effects, wave-wave interactions and coral strengths, the researchers said.

“In the aftermath of a destructive tsunami, there may be some things we could do to aid reef recovery after the more immediate needs onshore are tended to,” Yim said. “There’s probably not much we can do about the fine sediments that bury the coral, but we could perhaps clean up some of the larger debris and building materials like sheet metal roofing that cover up the coral. It’s a significant challenge.”

Collaborating on this research, which was published in Marine Geology, a professional journal, were Y.L. Young and D.L. Witt, scientists from the University of Michigan. The research was funded by the National Science Foundation and the video was produced by Paul Hillman of the National Oceanic and Atmospheric Administration.

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Solomon Yim, 541-737-6894