Lab’s Materials Preparation Center provided alloy for Planck Mission

For release: May 14, 2009

Contacts: 
Trevor Riedemann, Materials Preparation Center, 515-294-1366
Breehan Gerleman Luchessi, Public Affairs, 515-294-9750

AMES, Iowa – Materials produced at the U.S. Department of Energy’s Ames Laboratory were launched into space on May 14 with the European Space Agency’s Planck Mission. Ames Laboratory’s Materials Preparation Center synthesized over 20 kilograms of a lanthanum-nickel-tin alloy for use in a metallic hydride sorption cryocooler system—built by NASA’s Jet Propulsion Laboratory—that will cool instruments during the space mission.

The Planck satellite will collect precise measurements of Cosmic Microwave Background, the remnants of radiation that filled the universe immediately after the big bang. Scientists will use the data to help answer questions about how the universe began, how it evolved, and how it will continue to evolve.

The Materials Preparation Center not only cast the lanthanum-nickel-tin alloy for the Planck cryocooler systems, but it also produced the high-purity lanthanum and refined the nickel, all with the precision required to meet stringent purity and homogeneity specifications.

The project drew on a significant range of MPC skills: high-purity rare earths production, electron beam melting, arc casting, interstitial gas tests, electron-microprobe tests, metallography, rolling mill work, annealing furnaces.

Creating the materials was a big job. To ensure quality, MPC staff had to make the 20 kilograms in 50 gram batches, for a total of 400 batches.

Casting large amounts of the alloy caused inhomogeneity within ingots, and gas-atomized particles proved very homogenous but didn’t provide the needed performance, in this case. So, small ingots were created in an arc melter, a type of furnace that melts metals with a 400-500 amp electronic arc through argon gas. The components of the alloy posed another challenge: their varied melting points required some special preparation of the materials.

“We rolled the nickel and formed it into a dish-like shape. Then we put the tin and lanthanum in the nickel dish and heated the nickel from the edges,” says Trevor Riedemann, manager of the MPC’s rare-earth materials division. “As the nickel got hotter and hotter, the other two materials melted on the dish and created an intermediate intermettalic. From there, we melted the whole thing several times in the arc melter.

“Senior research technician Arne Swanson and John Wheelock, who is now retired, led the arc melting” says Riedemann, “But it was a chance for everyone at the MPC to do some arc melting or to weigh materials while someone else ran the arc melter, so we could get to make as many ingots as possible. It was a great project because it fully engaged the MPC, and everyone had a role.”

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University.  Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

 

###

 

hillr@ameslab.gov

Rhonda Hill

Clerk
Human Resources
Address

105 TASF
The Ames Laboratory
Ames, IA 50011-3020

Phone
515-294-2681
Email
hillr@ameslab.gov

deshong@ameslab.gov

Rhonda DeShong

Program Assistant
Human Resources
Address

105 TASF
The Ames Laboratory
Ames, IA 50011-3020

Phone
515-294-0931
Email
deshong@ameslab.gov

witt@ameslab.gov

Lynnette Witt

Assistant Manager, Human Resources
Human Resources
Address

105 TASF
The Ames Laboratory
Ames, IA 50011-3020

Phone
515-294-5740
Email
witt@ameslab.gov

muncrief@ameslab.gov

Diane Muncrief

Manager, Human Resources
Human Resources
Address

105 TASF
The Ames Laboratory
Ames, IA 50011-3020

Phone
515-294-5731
Email
muncrief@ameslab.gov

Ames Lab physicist observes novel liquid-like motion 
and nucleation in metallic nanostructures

For release: Feb. 11, 2009

Contacts:
Michael C. Tringides
, Division of Materials Science and Engineering, 515-294-6439
Breehan Gerleman Lucchesi
, Public Affairs, 515-294-9750 

AMES, Iowa – Imagine unloading a pile of bricks onto the ground and watching the bricks assemble themselves into a level, straight wall in only a few minutes. While merely a fantasy for builders in the everyday world, these types of self-assembled structures are a reality for those who build materials in the nanoworld. Michael C. Tringides, a senior physicist at the U.S. Department of Energy’s Ames Laboratory, has shown that nanoscale "straight wall" lead islands on silicon are spontaneously and quickly created by unusually mobile atoms.

Several years ago, Tringides’ research group was the first to observe that lead atoms deposited on a silicon surface at low temperatures self-organize into uniform-height island nanostructures. The laws of quantum mechanics – specifically, Quantum Size Effects – determine why lead atoms stack up to create uniform islands while other nanostructure systems organize into islands that vary in height.

How the lead-on-silicon islands organized into uniform-height islands remained a mystery until Tringides’ team made the surprising discovery that when lead atoms move along the surface of a silicon substrate, the lead atoms exhibit a liquid-like motion instead of the typical random-type diffusion observed in other systems. The liquid-like motion of atoms was observed using scanning tunneling microscopy at Ames Lab and low energy electron microscopy performed by collaborators in Hong Kong.

“One big surprise was that the atoms were moving a lot at such a low temperature: 150 degrees Kelvin or minus 123 degrees Celsius,” said Tringides.

“The other surprise was that the atoms weren’t moving randomly like individual atoms as we would expect. In this particular case, it seemed like the whole layer of lead atoms was moving like a liquid. Fluid-like motion of the lead atoms explains why the layer moves so easily and forms uniform islands so quickly.

“When applying nanotechnology, it’s very important to be able to make nanostructures of the same dimension using a method that others can easily replicate,” said Tringides. “And, it’s important that the growth process is fast.”

 Image

A single lead-on-silicon island (orange) grown over a substrate step. The island includes both 5-layer (stable) and 4-layer (unstable) heights and shows different nucleation as a function of layer height. An additional small amount of lead was added to test how new islands nucleate on top (the white “blobs”). The 4-layer height has many small islands while the 5-layer height has only a few large, fractal islands. Although the island is a single island with two connected parts, the two parts behave as if they are separate and each has different “reactivity.”

Tringides’ work succeeds in terms of uniformity and speed. The lead islands self-organize on silicon in only two to three minutes. Also, better understanding of how the lead islands grow will help researchers see if other systems show the same liquid-like behavior at low temperatures.

With such promising findings in hand, Tringides’ team, which includes associate scientist Myron Hupalo and graduate students Steven Binz and Jizhou Chen, further investigated the possible use of these unusual lead islands on silicon as templates to study typical atomic processes, such as adsorption, nucleation and atom bonding. These processes are important in the study of reactivity and catalysis.

During those experiments, Tringides’ group made another unexpected discovery. Normally atomic processes depend on an element’s chemical nature, but the group found that when it came to lead islands, quantum mechanics had another surprise in store: The atomic processes depend dramatically on whether the island height is odd or even rather than its chemical nature. Tringides’ group made this intriguing observation in a large lead island that had formed over a step on the original silicon surface. The top of the large island was flat as expected.

 Image

Lead atoms in liquid-like motion across a silicon substrate.  The black region is an area initially without lead, and the outside white area has a full layer of lead.  The four images represent snapshots of how the outside layer moves and fills the empty area.  (The difference in grey and white is because the new lead atoms that enter the empty area are not yet in their perfect sites.)  U.S. Department of Energy Ames Laboratory scientists, in collaboration with scientists from Hong Kong University of Science and Technology, were the first to observe this unique diffusion of lead atoms on a silicon substrate.

Play movie of lead-silicon diffusion

This video shows the remarkable diffusion of lead atoms on a lead-on-silicon island.  Here, the black region is an area empty of lead, and the region outside is a moving lead layer.  (The grey area is because the new lead atoms that enter the empty area are not yet in their perfect sites.)  Real-time for the video is 50 seconds and the temperature is negative 163 degrees Fahrenheit.  The video was created at Hong Kong University of Science and Technology using low-energy electron microscopy in collaboration with Ames Laboratory scientists.

Play movie of lead atom wetting

This video shows the unusual liquid-like motion of lead atoms on nanoscale lead-on-silicon islands.  The orange structures are islands, and the lighter color illustrates the movement of the lead atoms to the island’s top from the surrounding area.  Here, the lead atoms move on a five-layer island to create a seven-layer superstable island.  Real-time for the video is 15 minutes and the temperature is negative 28 degrees Fahrenheit.  The video was created at Ames Laboratory using a scanning tunneling microscope.

“But, the part of the island sitting on the higher terrace of silicon was four layers high, and the other part of the island sitting on the lower terrace was five layers,” said Tringides.

The group studied nucleation on this unusual island by adding a very small amount of lead to its surface, creating many new small islands on top of the large island. Examination revealed that the density of the new islands was 60 times higher on the four-layer part of the island than on the five-layer part even though the two parts of the island were connected, suggesting that atom bonding is easier on the four-layer islands.

“The island was made up of the same element, lead, throughout,” said Tringides. “So, we would expect the two parts of the island to communicate with each other, and atoms should be able to easily move from left to right and right to left among both halves of the island, so the density of the new small islands should have been the same in both parts.”

Instead, the two halves of the island behaved like two separate islands. The four-layer section of the island has similar characteristics to independent four-layer islands, and the five-layer section behaved like other five-layer islands.

“For the purpose of growing materials, the two-part island indicates that we may not have to change the element to create variation in material properties,” said Tringides. “Instead, we may be able to just change the height of the island.” “This is promising because it’s easier to change the geometry of an island than to go out and find a new, exotic material,” he added.

Tringides plans further experiments using gas adsorption to test the relationship between material reactivity and island height. The Department of Energy’s Office of Science, Basic Energy Sciences Office funded the work.

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University. The Lab conducts research into various areas of national concern, including the synthesis and study of new materials, energy resources, high-speed computer design, and environmental cleanup and restoration.

###

AMES, Iowa – Jerel Zerestky and Philip Ryan were part of a team, led by Argonne National Laboratory, that published an article in Nature Materials.  The article is titled “Enhanced Ordering Temperatures in Antiferromagnetic Maganite Superlattices.”  Zereskty performed neutron scattering measurements at the High Flux Isotope Reactor at Oak Ridge National Laboratory, and Ryan performed X-ray diffraction at the Advanced Photon Source at Argonne National Laboratory.

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University.  Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

###

Ames Laboratory and Catilin seek to commercialize new algal oil extraction process

For release: April 14, 2009

Contacts: 
Victor Lin, Ames Laboratory Chemical and Biological Sciences, 515-294-3135
Pamela Mahoney, Catilin, 650-854-7236
Kerry Gibson, Ames Laboratory Public Affairs, 515-294-1405

AMES, Iowa –Algae is widely touted as the next best source for fueling the world’s energy needs. But one of the greatest challenges in creating biofuels from algae is that when you extract the oil from the algae, it kills the organisms, dramatically raising production costs. Now researchers at the U.S. Department of Energy’s Ames Laboratory and Iowa State University have developed groundbreaking “nanofarming” technology that safely harvests oil from the algae so the pond-based “crop” can keep on producing.

Commercialization of this new technology is at the center of a Cooperative Research and Development Agreement between the Ames Laboratory and Catilin, a nano-technology-based company that specializes in biofuel production. The agreement targets development of this novel approach to reduce the cost and energy consumption of the industrial processing of non-food source biofuel feedstock. The three-year project is being funded with $885,000 from DOE’s Office of Energy Efficiency and Renewable Energy's Industrial Technology Program as part of the 2008 Nanomanufacturing for Energy Efficiency program, and $216,000 from Catilin and $16,000 from Iowa State University in matching funds.

The so-called “nanofarming” technology uses nanoparticles to extract oil from the algae. The process doesn’t harm the algae like other methods being developed, which helps reduce both production costs and the production cycle. Once the algal oil is extracted, a separate and proven solid catalyst from Catilin will be used to produce ASTM (American Society for Testing and Materials) and EN certified biodiesel.

 The potential of algae for fuel is tremendous as up to 10,000 gallons of oil may be produced on a single acre of land.(1)    According to other estimates, if fuel from algae production replaced all the petroleum fuel used annually for ground transportation in the United States, it would require only 15,000 square miles – or half the size of South Carolina – to produce that quantity of algal-based fuel,(2)   or just less than 70 percent of the total corn acreage in Iowa for 2007.(3)

The driving force behind this combination of nanotechnology and biofuels is Ames Laboratory Chemical and Biological Sciences Program Director Victor Lin.  Since 2000, Lin, who is also a chemistry professor at Iowa State University, has been leading research on using nanotechnology to dramatically change the production process of biodiesel. This successful technology led Lin to found Catilin one and a half years ago. 

“By combining nanotechnology, chemistry and catalysis, we have been able to find solutions that have not been considered to date,” Lin said. “Ames Laboratory and Iowa State University offer valuable research capabilities and resources that will play a key role in this exciting collaboration with Catilin.”

According to Marek Pruski, Ames Laboratory senior physicist and co-investigator on the project, phase one and two of the project will cover the culturing and selection of microalgae as well as the development of the specific nanoparticle-based extraction and catalyst technologies for the removal of algal oil and the production of biodiesel, respectively. Phase three will focus on scale-up of the catalyst and pilot plant testing on conversion to biodiesel. 

“When we ultimately put together this exceptional extraction technology with Catilin’s existing solid biodiesel catalyst, we will dramatically increase the reality of renewable energy,” said Catilin’s CEO, Larry Lenhart.  “Given the Obama administration’s objectives, the timing is perfect.”

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University.  Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

###

About Catilin
Catilin, Inc. is a technology-based company that is revolutionizing biofuel production.  Catilin has developed a unique, new technology for biodiesel production that greatly reduces the cost of producing a gallon of biodiesel while creating a superior quality biodiesel and glycerin byproduct.  Catilin’s patent-pending non-toxic technology is centered on a family of solid heterogeneous catalysts that can be easily used within existing production facilities, can be reused multiple times and works with virtually every biodiesel feedstock source.

In addition, several production steps in the traditional biodiesel production process can be eliminated with Catilin’s revolutionary technology, making the process both economically and environmentally more desirable, while producing purer biodiesel and a purer glycerol side-product.

 The pioneering research of Catilin, in conjunction with Ames Laboratory and Iowa State University, continues to focus on the future of biodiesel, including the award-winning research on algae to biodiesel.

  1. -  “Potential for Biofuels from Algae,” Philip T. Pienkos, National Renewable Energy Laboratory, presented at the Algae Biomass Summit, Nov. 15, 2007, San Francisco, CA.
  2.  “Widescale Biodiesel Production from Algae,” Michael Briggs, University of New Hampshire, Physics Department, 2004.
  3. USDA & Iowa State University Extension Service.

Magnetic refrigeration conference to draw international audience

For release: May 7, 2009

Contacts: 
Karl Gschneidner, Materials Sciences and Engineering, 515-294-7931
Vitalij Pecharsky, Materials Sciences and Engineering, 515-294-8220
Kerry Gibson, Public Affairs, 515-294-1405

AMES, Iowa – Researchers and industry representatives in the refrigeration and air conditioning field will converge in Des Moines later this month to discuss and promote the cause of magnetic refrigeration at the 3rd International Conference on Magnetic Refrigeration at Room Temperature – known in the business as Thermag III. The focus of the four-day event will be on an energy efficient form of refrigeration that replaces gas compressors and ozone-depleting refrigerants with a system that uses special alloys and a magnetic field to provide the cooling and environmentally benign coolants to circulate that cooling power through the refrigeration loop.

“Modern compression/expansion refrigeration cycle cooling is a high-energy-demand industry that annually consumes as much as 15 percent of the total electrical energy produced,” said conference organizer Karl Gschneidner, a senior metallurgist at the U.S. Department of Energy’s Ames Laboratory. Gschneidner is an Anson Marston Distinguished Professor at Iowa State University, a pioneer in magnetic refrigeration and a world-renowned expert in the rare-earth metals used in the technology.

“Magnetic cooling and refrigeration is 20 to 30 percent more energy efficient than conventional vapor-compression refrigeration,” Gschneidner said, “The magnetic refrigerants are solids, so the hazardous, ozone-depleting and greenhouse chemicals are completely eliminated, making magnetic refrigeration one of the few, positively clean technologies.”

Hosted by Ames Laboratory and the College of Engineering, the Office of the Vice President for Research and Economic Development, and the Department of Materials Science and Engineering, all at Iowa State University, the conference will feature presentations from around the globe on emerging trends and research in magnetic refrigeration. Keynote speakers include researchers from the United States, Canada, the United Kingdom and Spain, and the program also includes invited speakers from Denmark, France, Russia, Japan, Spain and the United States.

The conference, which will be held at the Embassy Suites in downtown Des Moines, opens on Tuesday, May 12. The daily program will include a keynote address and invited talks, along with oral and poster presentations on current research in the field. Participants are also scheduled to travel to Ames and tour research facilities at Ames Laboratory and Iowa State University on May 13. The conference concludes on May 15.

Also, the first operational laboratory prototype magnetic refrigerator will be on display. It was built by Astronautics Corporation of America, Milwaukee, Wis., with assistance from Ames Laboratory scientists who worked on the magnetic refrigerant materials. For more information on the conference, including a detailed program and speaker information, check out the conference Web site at www.ucs.iastate.edu/mnet/thermag/home.html.

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University.  Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

 

###

(NOTE TO MEDIA: If you are interested in interviewing the conference organizers or any of the keynote speakers, please contact Kerry Gibson, Ames Lab Public Affairs at 515-294-1405, kgibson@ameslab.gov.)

 

Victor Lin’s nanoscale research a most-cited work
in the journal Chemical Communications

For release: Sept. 14, 2009

Contacts: 
Victor Lin, Chemical and Biological Sciences, 515-294-3135
Kerry Gibson, Public Affairs, 515-294-1405

AMES, Iowa – A paper by Victor Lin, Chemical and Biological Sciences program director at the U.S. Department of Energy’s Ames Laboratory, has been recognized among the most-cited papers published in the journal Chemical Communications. Lin was honored at an Aug. 16 dinner in Washington, D.C., being held in conjunction with the American Chemical Society’s Fall National Meeting and Exposition.

Lin’s paper, “Mesoporous silica nanoparticle based controlled release, drug delivery, and biosensor systems,” was recognized among the top 10 most-cited articles that were published in 2007, according to the 2008 Thomson Reuters Journal Citations Reports. The article, which was co-authored by Brian Trewyn, Ames Laboratory associate, and Iowa State University graduate students Igor Slowing and Supratim Giri, appeared in the April 2007 issue of Chemical Communications, published by the Royal Chemical Society. The ChemComm Web site lists 22 separate papers to date that have cited the original paper by Lin and his research group.

Lin has extensively researched the sponge-like nano-scale particles for not only drug delivery, but as a harvesting mechanism for removing bio-oils from algae and a structure for introducing nanoscale catalysts into chemical reactions, dramatically increasing the overall surface area of the catalysts due to the small size and vast quantities of the catalyst particles available.

Ames Laboratory is a U.S. Department of Energy Office of Science laboratory operated for the DOE by Iowa State University.  Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global challenges.

###