Skip to Main Content U.S. Department of Energy
Breakthroughs Magazine

Solutions Update

Sometimes smaller is better

A research team from the Pacific Northwest National Laboratory, Oregon Health and Science University, University of Minnesota and the University of Idaho is studying the ability of nanoscale iron particles to reduce carbon tetrachloride, a common groundwater contaminant.

In the past, carbon tetrachloride was a common component in refrigerants, industrial degreasers and pesticides. This chemical is now an environmental contaminant, and according to the U.S. Environmental Protection Agency, carbon tetrachloride can cause liver, kidney and central nervous system damage.

One remediation method for contaminated groundwater uses microsized iron particles that react on contact with carbon tetrachloride. However, the reaction often produces chloroform, another environmentally undesirable chemical.

The research team's studies indicate that one type of nanosized iron particle can be more effective in reducing carbon tetrachloride in water than the microsized particles while also minimizing the production of chloroform.

"The use of nanosized particles of iron for cleaning up contaminants in groundwater, soil and sediments is an exciting new technology that contributes to a general enthusiasm about nanotechnology," said Don Baer, the project's principal investigator from PNNL.

The researchers examined two iron nanoparticles, one produced by the hydrogen reduction of an iron oxide (FeH2) and the other produced by a solution synthesis (FeBH) method. The FeH2 particles had a shell made of iron oxide, and the FeBH had a shell that included boron oxide as well as iron oxide. The research study involved both the characterization of the particles and examination of their reactivity. The team determined that FeH2 produced lower quantities of chloroform in comparison to FeBH or micron-sized particles of iron.

This study suggests that nanosized iron particles with the right chemistry may be the better ingredient for new technologies to clean up carbon tetrachloride in contaminated groundwater sites around the country.

(Photo caption: This high-resolution transmission electron microscopy image of a metallic iron nanoparticle shows the nature of its "protecting" shell. The chemistry of the shell appears to be crucial to the nanoparticle's ability to react with carbon tetrachloride to produce harmless byproducts.)

Structural safety gets boost from new technology

An acoustic inspection technology developed at Pacific Northwest National Laboratory may help users in the oil, gas and other industries decide if a metal structure can withstand normal operation. Using a newly developed ultrasonic measurement technology, PNNL researcher Paul Panetta and his team can rapidly locate and characterize suspected damage associated with strained metal, which current technologies cannot do.

"The immediate beneficiaries of the technology are oil and gas pipeline operators because our prototype is specifically configured for characterizing damage to pipelines from landslides, earth movement and dents," Panetta said. "Its distinctive capabilities can enhance existing inspection technologies to help avoid pipeline failures—sometimes catastrophic ones."

A bend, bulge or dent in a pipeline or other metal structure is sometimes obvious, but the extent of the damage is not. This measurement technology uses ultrasound to determine the material properties of metal to determine the extent of damage caused by natural disasters, accidental run-ins with heavy equipment or normal wear and tear.

"Pipes are typically assessed with in-line inspection tools, commonly referred to as 'pigs' in the oil and gas industry," Panetta said. "Pigs typically only show wall thinning or detect the presence of dents, which may not indicate if the damage is detrimental."

The technology can be used for assessing the integrity of pipelines, bridges, railroad tracks and cars, steel girders, airplane landing gear or other metal structures. It was originally developed for the Department of Energy for use in natural gas pipelines and is currently available for licensing.

(Photo caption: A prototype manual scanner of the ultrasound pipe crawler is tested on a metal pipe by researchers from the Pacific Northwest National Laboratory. This technology is designed to help users in the oil, gas and other industries determine the integrity of metal structures.)

ScalaBLAST solves problems in record time

"Remember that time is money." – Benjamin Franklin

Scientists are dedicated to making discoveries that influence our world, but making these discoveries takes time. It took Albert Einstein 16 years to express his general theory of relativity. Benjamin Franklin was first introduced to electricity experiments on a trip to Boston in 1746, but his famous lightning rod experiment didn't occur until six years later—and he knocked himself unconscious more than once in the process. Of course, Al and Ben didn't have the luxury of computing technologies and tools either.

Today we have ScalaBLAST, a computational tool developed at the Pacific Northwest National Laboratory based on BLAST, a conventional sequence analysis tool developed by the National Center for Biotechnology Information (NCBI). ScalaBLAST is dramatically speeding up our understanding of the machinery of life—bringing us one step closer to curing diseases, finding safer ways to clean up the environment and protecting the country against biological threats. ScalaBLAST uses innovative high-performance computing software such as the Global Arrays Toolkit to perform sophisticated sequence alignment of proteins. Now, large-scale problems—such as the simultaneous analysis of hundreds of organisms—can be solved in hours rather than years.

Recently, PNNL scientists completed a large-scale ScalaBLAST analysis in conjunction with the Joint Genome Institute at Lawrence Berkeley National Laboratory, solving a significant "data avalanche" problem for JGI. In just 18.5 hours, 1.6 million proteins were BLASTed against NCBI's nonredundant protein database using 1500 processors, producing 75 gigabytes of analysis results-a job that would have taken just over 3 years on a single machine.

Hold onto your seats—PNNL scientists are BLASTing us into an exciting future of scientific discovery through this and other innovations extracted from the Department of Energy Office of Advanced Scientific Computing Research Data Intensive Computing for Complex Biological Systems project. But unlike Benjamin Franklin, we won't have to knock ourselves unconscious to ride along.

(Photo caption: ScalaBLAST gives a sizeable performance boost over BLAST, a conventional sequence analysis tool.)

Uniform nano-clusters signal improved catalysts

A new model system of nano-structures has been synthesized and could lead to control of chemical transformations critical for enhancing the nation's energy future.

This new nanostructure model system, developed by researchers at the Pacific Northwest National Laboratory, the University of Texas-Austin (UT) and Washington State University, offers insights into the structure and reaction mechanism of metal oxides. Metal oxides are important catalysts for producing fuels for transportation and value-added chemicals.

In the new model system, nano-clusters composed of cyclic tungsten trioxide line up molecule-by-molecule on a titanium dioxide platform. One tungsten atom from each cluster is raised slightly, holding forth the potential to execute catalytic reactions—a striking difference from commercial catalysts. Commercial catalysts vary in size and chemical composition, making it difficult to understand or predict the reactions taking place at the molecular level. In the new model, all the nano-clusters are the same size, evenly dispersed, and oriented in one of two directions on the titanium oxide crystal layer. This unique, uniform feature may enable scientists to predict with increased accuracy and control the reactions that will occur, thereby enhancing the effectiveness of catalytic reactions.

The researchers employed specialized equipment at the Environmental Molecular Sciences Laboratory, a DOE user facility on the PNNL campus, to prepare and characterize the platform as well as the clusters. Using a unique approach that changed the tungsten oxide directly from a solid to a gas, the researchers successfully stabilized the molecular rings—or "trimers" —of tungsten on the titanium platform.

The new nanostructure model system was developed as part of the Early Transition Metals as Catalysts project at PNNL, supported by the DOE Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division.

(Photo caption: A scanning tunneling microscope image (left) shows nano-clusters deposited on a titanium dioxide platform with consistent orientation of the atoms (right). The dark triangle indicates the center of the tungsten trioxide molecular ring on the platform; the brighter side depicts the raised atom.)

Breakthroughs Magazine

In this issue...