2009ISSUE 2

SCIENCE & TECHNOLOGY AT THE AMES LABORATORY
FEATURES

6 Harnessing the Casimir Effect Costas Soukoulis, Ames Laboratory’s expert in metamaterials, helps uncover new 

 information on the Casimir effect.

7 Improving the Grid with Stronger Power Lines 

 Ames Laboratory researchers are working to develop a new alloy that will make 

 power lines stronger and able to carry more current.

8 Solid-state NMR Central An unusual concentration of expertise in solid-state nuclear magnetic resonance 

 spectroscopy is not only helping characterize new materials, it’s putting Ames 

 Laboratory at the forefront in pushing the technology’s envelope.

12 Stirring up Greener Crops Evidence is pointing to an unexpected benefit of wind power — wind 

 turbines may help keep surrounding crops greener.

14 What I Did on My Summer Vacation Middle School teachers make “science” their summer project.

 

DEPARTMENTS

3 Director’s Letter

4 Awards

Ames Laboratory is a U.S. Department of 

Energy laboratory seeking solutions to energy-related problems through the exploration of chemical, engineering, materials 

and mathematical sciences, and physics. 

Established in the 1940s with the successful development of the most efficient 

process to produce high-purity uranium 

metal for atomic energy, Ames Lab now 

pursues much broader priorities than the 

materials research that has given the Lab 

international credibility. Responding to issues of national concern, Ames Laboratory 

scientists are actively involved in innovative 

research, science education programs, the 

development of applied technologies and 

the quick transfer of such technologies 

to industry. Uniquely integrated within a 

university environment, the Lab stimulates 

creative thought and encourages scientific 

discovery, providing solutions to complex 

problems and educating and training 

tomorrow’s scientific talent.

Steve Karsjen, Public Affairs Director

Kerry Gibson, Editor

Breehan Gerleman Lucchesi and 

Mark Ingebretsen, Contributing Editors

Grant Luhmann, Art Director

Katherine Rohlfing, Graphic Designer

Copyright 2009 by Ames Laboratory. All 

rights reserved. For additional information 

about Ames Laboratory or topics covered 

in this publication, please contact: 

Editor, Inquiry

Ames Laboratory

111 TASF

Ames, Iowa 50011-3020

515-294-9557

www.ameslab.gov

Inquiry is published biannually by the Ames 

Laboratory Office of Public Affairs. Iowa 

State University operates the Laboratory 

for the U.S. Department of Energy under 

contract DE AC02 07CH11358. Ames 

Laboratory shares a close working relationship with Iowa State University’s Institute 

for Physical Research and Technology, a 

network of scientific research centers.

Contents

Cover: Ames Laboratory has three different solid-state nuclear magnetic resonance 

research groups represented by group leaders Klaus Schmidt-Rohr (left), Marek Pruski 

(center) and Yuji Furukawa. While the group posed with equipment in Pruski’s lab, 

each group has its own lab space, equipment and scientific specialty when it comes 

to using NMR technology. 

Back cover: A closeup of control knobs on an NMR probe.

7

ENERGY

U.S. DEPARTMENT OF Office of

Science

8

12

14

6
From the Director

INQUIRY Issue 2 • 2009 3

he Ames Laboratory is home to a range of “best in class” scientific 

research projects, and it also applies the highest levels of scientific 

expertise to developing solutions for today’s great challenges — including the development of the next generation of world-class scientists.

Nuclear magnetic resonance or, NMR, has been used to study the 

structures of materials for many decades. It is a mature tool, so you can buy a 

pretty sophisticated NMR spectrometer right “off the shelf” and get some very nice results almost 

at the push of a button. But Ames Lab researchers are involved at a different level. We have 

developed solid-state NMR techniques that push the extremes of the method in several different 

directions: the world’s fastest sample rotation (as well as strategies to overcome the limitations of 

finite speed!), the coldest samples, and 

the most sophisticated experimental 

strategies to make non-routine or seemingly impossible analyses routine at the 

Ames Laboratory. 

Our researchers are defining the future of solid-state NMR as a tool for materials analysis. This advanced work helps us to apply 

NMR to problems of real importance in areas such as fuel-cell membranes and thermoelectrics.

In this issue of Inquiry, you will find some stories that focus on our world-leading, solid-state 

NMR research and on other fundamental science, such as the Casimir effect in metamaterials. 

You will also be able to see how our science is helping to extract energy from the wind and deliver 

it through an advanced electrical grid, and read about an exciting program that helps teachers 

inspire young minds about science.

Read on, and be inspired!

T

From the Director

Alex King, Director

Welcome to Ames Laboratory, 

home of “world-leading science”
4 INQUIRY Issue 2 • 2009

 a AWARDS

Pat Thiel, Ames Laboratory senior chemist, has 

been selected for major awards from both the 

American Chemical Society and the American Physical Society. She was named winner of the 2010 

Arthur W. Adamson Award for Distinguished Service in the Advancement of Surface Chemistry. Following on the heels of that 

announcement, she was also selected for the APS 2010 David 

Adler Lectureship Award, which recognizes her as an outstanding 

contributor to the field of material physics, who is noted for the 

quality of her research, review articles and lecturing.

 Thiel, who is also an Iowa State University Distinguished 

Professor in chemistry and materials science and engineering, 

will receive the Adamson Award during 

the 239th ACS national meeting in San 

Francisco in March 2010. The award 

consists of $5,000 plus travel expenses, 

a medallion with a presentation box and a certificate. The medallion will be presented during the award address.

According to Thiel, a symposium will be held in her honor 

at the ACS national meeting. The Adamson award was first presented in 1993, and past recipients have been distinguished 

Gordon Named ACS Fellow

Mark S. Gordon, director of the Applied Mathematics and 

Computational Sciences program at Ames Laboratory, was 

named to the inaugural class of American Chemical Society 

Fellows. Gordon, who is also a senior chemist at Ames Lab 

and a Distinguished Professor of Chemistry at Iowa State 

University, joined 161 other chemistry researchers who received the honor when the group met in Washington, D.C. 

this past August.

“Some of the foremost names in U.S. chemistry are on 

this list, including Nobel Laureates and members of the 

National Academy of Sciences,” Gordon says. “It is a great 

honor to be included with these folks.”

Gordon was also the recipient of the 2009 ACS Award for 

Computers in Chemical and Pharmaceutical Research. The 

international award recognizes outstanding achievement in 

the use of computers in research, development or education in the chemical and biological sciences.

Gordon’s research focuses on 

using high-performance computing to understand how molecules 

and atoms act, interact and react. 

He has devoted much of his career 

to developing the General Atomic 

and Molecular Electronic Structure 

System, or GAMESS, software suite, 

which is designed to run on massively parallel supercomputers. 

Such systems execute trillions of 

calculations per second. GAMESS, 

which has an estimated 100,000 users, can perform highlevel modeling of complex physical, chemical and biological 

systems. Gordon’s GAMESS work has been funded by the 

DOE’s Office of Advanced Computing Research.

researchers in the field, including David King, the 2009 award 

winner, who was science advisor to former British Prime Minister 

Tony Blair. Thiel holds the distinction of being the first woman 

selected for the award. 

She will receive the Adler award at the APS 2010 March 

Meeting in Portland, Ore. The award consists of $5,000, travel 

expenses to the conference and a certificate. The certificate will 

note that Thiel is honored “for seminal contributions to surface 

structure and dynamics of complex metallic alloys, including 

quasicrystals and kinetically limited growth and relaxation of 

nanostructures in thin metal films.” Thiel will also deliver an invited talk at the APS meeting.

“Pat is an outstanding researcher as indicated by the many 

awards she has won,” says Ames Laboratory Director Alex King. 

“The Adler Award reflects something that we take special pride 

in at the Ames Laboratory. Although Pat is most often recognized as a chemist or a materials scientist, this award comes 

from the American Physical Society, and that speaks to the interdisciplinary nature of Pat’s work. We value interdisciplinary research highly at the Ames Laboratory, and Pat Thiel exemplifies 

it at the very highest level.”

Thiel Wins ACS and APS Awards Pat Thiel

Mark S. Gordon
INQUIRY Issue 2 • 2009 5

Two Ames Laboratory 

researchers won a 2009 

R&D 100 Award for software that will help engineers design the next generation of highly efficient 

and low-emission power 

plants.

The software, developed 

by Mark Bryden, program 

director for Ames Lab’s 

Simulation, Modeling and Decision Science program, and Doug 

McCorkle, associate scientist at Ames Lab, enables engineers 

to review and revise proposed designs more quickly, more efficiently and at less cost than ever before by integrating different 

types of engineering data into one virtual environment.

Often called the “Oscars of invention,” the R&D 100 Awards 

are presented annually by R&D magazine for the top 100 products of technological significance.

This is the 17th R&D 100 Award won by Ames Laboratory 

scientists. The 2009 R&D 100 Award is the second for Bryden 

and McCorkle, who along with colleague Gerrick Bivens, also 

won in 2006 for another virtual engineering software application.

“We are honored to have our work recognized by a 2009 

R&D 100 Award,” says Bryden. “It has been exciting working with 

a collaborative research team to develop and bring to market 

new engineering tools that can help address the need for new 

and creative energy solutions.”

Cochran Receives NSF Career Award

Eric Cochran, associate scientist at Ames Laboratory, received 

a National Science Foundation CAREER award, the organization’s most prestigious award for junior researchers.

The NSF CAREER award recognizes researchers who exemplify the role of teacher-scholars through outstanding research, 

excellent education and the integration of education and research. The five-year, $475,000 award will support Cochran’s 

research work in Iowa State University’s chemical and biological engineering department. Cochran will explore a new class 

of self-organizing block copolymer nanocomposites based on 

polymer-tethered clays.

“I am excited and honored 

that the NSF has chosen to support this research through the 

CAREER award,” says Cochran. 

“This is an important opportunity 

to explore a unique system of 

materials with potential for enormous impact in the field of polymer physics. Through this grant, I 

will also be better able to share 

my enthusiasm for research with 

teachers and students throughout Iowa.”

At Ames Laboratory, Cochran is part of an interdisciplinary 

research team that is integrating polymers and nanoscale particles to create self-assembling materials for use in solar cells 

and hydrogen fuel cells. The work is funded by Ames Laboratory’s royalty income seed funding program.

Eric Cochran

for Virtual Engineering Software

Bryden and McCorkle

R&D 100 Award
6 INQUIRY Issue 2 • 2009

apart. As a consequence, an attractive force exists that prompts 

the plates to come closer together.

Soukoulis, who is also a Distinguished Professor of Liberal Arts 

and Sciences at Iowa State University, and his team wanted to 

do just the opposite: harness a 

Casimir force within the gap, capable of pushing the two plates 

apart. This repulsive Casimir 

force might have an important 

practical purpose. Namely, it 

could be used to overcome 

something called van der Waals 

forces that are the bane to engineers. Van der Waals forces – think of them as Casimir waves 

– are minute. But in nanoscale environments they’re strong 

enough to cause tiny devices to permanently lock up. 

To induce their repulsive force, the researchers turned to chiral 

metamaterials, artificial substances that can change the characteristics of energy waves when those waves are reflected off them. 

Some weak chiral materials, such as sugar, can be found in nature, but only artificial metamaterials allow for the much stronger 

chirality required to obtain a repulsive Casimir force. Whether 

natural or artificial, chiral materials share a common, albeit somewhat peculiar, trait: their molecular structure is such that they cannot be superimposed on a mirror image of themselves.

Because the chiral materials Soukoulis’ team studied were 

artificial, they could be engineered so that waves reflected off 

them cause the energy in the gap to decrease when the plates 

are pulled apart, exerting a repulsive Casimir force within the 

gap separating the two plates, in contrast to the usually attractive Casimir force. This is made possible due to the additional 

degree of freedom that crosscouples electric and magnetic fields 

in chiral materials. 

If those plates had instead been the moving parts of a nanomachine coated with chiral metamaterials, the repulsive force 

generated by the metamaterials theoretically would have neutralized the van der Waals forces, causing the moving parts to 

operate essentially without friction. 

Creating chiral metamaterials is expensive and difficult. So the 

researchers demonstrated their work via a complex mathematical equation. And while the team isn’t sure if the amount of 

repulsive force they’ve harnessed is enough to overcome van 

der Walls forces in nanodevices, they’ve succeeded in opening 

a new direction of research that may greatly expand the role of 

nanotechnology someday, while making the quantum realm a 

little less mysterious. 

N THE MYSTERIOUS REALM OF QUANTUM MECHANICS, 

nothing is as it seems. Even a totally dark vacuum has been 

shown to be teaming with energy of virtually every possible 

wavelength. Scientists know this because of a phenomenon called the Casimir effect, named after Hendrik Casimir, 

the Dutch physicist who discovered it in the late 1940s.

More recently, Costas Soukoulis, senior physicist at the Ames 

Laboratory, along with Ames Lab assistant scientist Thomas Koschny and their colleagues elsewhere, discovered a way to harness the Casimir effect using an exotic class of materials known 

as chiral metamaterials. The results were published in the Sept. 

4, 2009 issue of Physical Review Letters, in an article entitled, 

“Repulsive Casimir Force in Chiral Metamaterials.”

The group’s work, which could one day make nanoscale 

machinery operate in a virtually frictionless environment, has already netted considerable interest in the scientific world. During 

a recent presentation in London, Soukoulis was bombarded with 

I

Q

Harnessing

BY MARK INGEBRETSEN theCasimir Effect

fellow physicists’ questions. And for good reason. Besides being 

the first to suggest that chiral metamaterials were capable of inducing a repulsive Casimir force, the team joins a small group of 

scientists who’ve been able to manipulate the elusive force at all. 

Casimir theorized that if you placed two objects — plates, for 

example — close to one another inside a vacuum, the longer 

wavelengths of the electromagnetic field present even in the 

vacuum due to Heisenberg’s uncertainty principle would be 

blocked, since they couldn’t fit between the small gap separating 

the plates. The smaller the gap, the fewer modes fit. Thus, the 

amount of energy density inside the gap decreases as the size 

of the gap decreases. So work has to be done to pull the plates 

Costas Soukoulis
aluminum/titanium composite would be 

cost prohibitive. 

So the two scientists discussed alternatives, and Anderson suggested using different aluminum/transition metal powder 

blends to try to create the same reinforced 

microstructure. Over the past 10 months, 

the two scientists have experimented with 

a variety of powder processing and deformation processes. 

“Results so far are looking promising,” 

says Anderson. “We’ve had limited success and we’re looking forward to the next 

several months to answer our questions.” 

Beyond high strength and high conductivity, the aluminum/transition metal composite must have an additional and critical 

benefit, which is its cost. The metal should 

be “dirt cheap” compared to titanium, says 

Anderson, which is a tremendous benefit 

when you think of placing thousands of 

miles of additional power line across the 

Midwest to expand the electrical grid. 

“Developing a stronger cable material 

might allow us to locate these towers 50 

percent farther apart,” says Anderson. “Just 

imagine the savings that could be generated in materials and land costs.” 

INQUIRY Issue 2 • 2009 7

HE STATE OF IOWA IS WINDY. 

In fact, Iowa is the second 

largest generator of wind 

power in the country behind 

Texas. Iowa is also blessed by 

its geographical location close to population centers like Chicago that have an 

insatiable appetite for electricity. The 

question is how to get the electricity from 

Iowa’s wind turbines to power centers 

over today’s power lines. Currently, that’s 

not easy because there isn’t enough electrical-grid capacity, which means there 

aren’t enough south-to-north power lines 

to carry the electricity. 

And there are other problems. The 

cables you see strung from those massive poles dotting the landscape are old. 

Many of them have been hanging there 

for 20-25 years. And there are strict limits 

on how much current the existing lines 

made of aluminum and steel can carry. 

That’s because too much power load on 

the lines actually causes them to heat 

up, causing the aluminum conductors 

to expand and weaken; then sag — a 

hazard in its own right. Finally, there’s 

the expense involved in stringing more 

power lines in order to expand the electrical grid. 

Expanding the grid is a problem that 

must be addressed nationally, especially since the Obama administration 

is calling for 20 percent of the nation’s 

electrical power to be derived from 

wind power by 2030. But other parts 

of the grid issue, such as how to build 

stronger cables out of cheaper materials while maintaining high electrical 

conductivity, are being addressed at the 

Ames Laboratory. 

“We have an opportunity to produce the next generation of high-power 

transmission cable,” says Iver Anderson, Ames Lab senior metallurgist.

Anderson has joined forces with 

Ames Lab associate scientists Alan Russell and Scott Chumbley to take a new 

look at some old research that could 

lead the way in cable design. Some 

time back, Russell developed a highstrength aluminum matrix conductor 

made from pure aluminum reinforced 

with pure titanium. He found that during deformation to shape the bar into 

wire, the titanium particles strung out 

into thin ribbons throughout the microstructure and reinforced the aluminum. 

The result was a strong material with 

high conductivity. Although this could 

have solved the problem of sagging cables, it brought about a new problem: 

titanium powder is quite expensive, so 

making transmission lines out of an 

For licensing information:

Mary Kleis, (515) 294-3893

mkleis@iastate.edu 

Research funded by:

Ames Laboratory royalty income seed funding program

This micrograph shows how transition 

metal particles can be strung out into 

thin ribbons throughout the host material. These ribbons add strength to the 

composite material.

Aluminum/transition metal composite may improve cable 

strength and conductivity, while reducing manufacturing costs 

This electrical cable consists of seven 

stainless steel wires in the center, 

wrapped by 26 aluminum wires. The 

steel provides strength; the aluminum 

is a good electrical conductor.

Iver Anderson inserts a piece of wire into a 

swaging unit to reduce its diameter, which 

deforms the microstructure and forms 

ribbon-like metal fiber reinforcements.

Next-generation Power Cables

T

Q

BY STEVE KARSJEN
8 INQUIRY Issue 2 • 2009
INQUIRY Issue 2 • 2009 9

U C L E A R M A G N E T I C 

resonance spectroscopy is 

a complex, highly specialized field where researchers study the spin resonance of the atomic nuclei in materials 

to understand the molecular properties of 

those materials. That Ames Laboratory 

would use this technology in the characterization of new materials isn’t surprising. 

But the fact that Ames Laboratory has 

three solid-state NMR research groups, 

especially for a research facility its size, is 

fairly unique.

The three groups – headed by Marek 

Pruski, Klaus Schmidt-Rohr and Yuji Furukawa – also have their own specialized 

uses for the technology. In Pruski’s case, 

he’s using it to study catalysts and other 

complex inorganic and organic materials. 

Schmidt-Rohr is applying the technology 

to understand the structure of fuel-cell 

membranes, nanocomposites, complex 

organic matter, and thermoelectric tellurides. For Furukawa, it’s an important tool 

for understanding the magnetic and electronic properties of materials, such as low 

dimensional spin systems and superconductors, at extremely low temperatures.

It’s all about spin 

The technology is based on the principle that the nucleus of an atom of material that contains an odd total number of 

protons and neutrons will have a nonzero 

angular momentum, or spin, and a magnetic moment. This magnetic moment 

acts similar to a bar magnet in that it feels 

the effects of static and radio-frequency 

magnetic fields. It rotates around the field 

with a frequency that is directly proportional to the magnetic field at the nucleus. 

This frequency, which can be measured 

with an accuracy of better than 1 in 100 

million, probes the local magnetic fields 

generated by surrounding electrons 

and other nuclear spins, and thus can 

provide detailed information about the 

physical and chemical properties of the 

material, such as the distance between 

nuclei and their specific positions at a 

particular point in time.

In liquids, the fast, random motion 

of the molecules averages out many of 

the interactions of the spins, resulting in 

narrow spectral lines. Solids, however, 

present more of a challenge because 

the molecules are basically locked in position, so anisotropic, or orientation-dependent, interactions affect the nuclear 

spins, resulting in broad spectral lines. 

To get better resolution, NMR specialists 

use some “tricks” to make the solid react more like a liquid, thereby producing 

high-resolution frequency spectra.

One such solid-state NMR technique 

mechanically spins the sample at high 

speed at the so-called “magic angle,” 

which can effectively reduce some of 

the spin interactions, including the coupling between the magnetic moments 

of neighboring nuclei. Taking this a 

step further, researchers also use radiofrequency irradiation to achieve better 

control over the spin interactions. These 

strategies are used in various multiresonance and multidimensional schemes, 

which in concert with continuing advances in theory and instrumentation 

afford additional gains in sensitivity and 

resolution. And Ames Lab’s NMR specialists are helping push the envelope. 

Still evolving

“NMR is a fascinating field that, at 

65-years-old, is still changing and evolving,” Pruski says, “often on a monthly 

basis. We’re not just users of fancy maAmes Laboratory’s has an unusual concentration of nuclear magnetic resonance expertise

chines, we’re helping advance the technology, and it’s that constant push that keeps 

me excited about the work we’re doing.”

For example, Pruski‘s group is exploiting improved homo- and hetero-nuclear 

correlation experiments for spin-1/2 nuclei, where significant enhancements in 

resolution and sensitivity are accessible 

due to recent advances in ultrafast magic angle spinning. In this case, ultrafast 

means 3 million rpm! In fact the group is 

working with an equipment manufacturer 

on prototypes for new NMR probes that 

utilize this new technology. 

Schmidt-Rohr’s group has worked 

to tailor NMR techniques to specifically 

study nanocomposites using the exotically 

named HARDSHIP (HeteronucleAr Recoupling with Dephasing by Strong Homonuclear Interactions of Protons) and SUPER 

(Separation of Undistorted Powder patterns 

by Effortless Recoupling). Schmidt-Rohr’s 

group has also introduced new methods 

for quantitative analysis of scattering data of 

nanostructured materials. 

Q

N

BY KERRY GIBSON

(opposite) The “business” end of a NMR probe. Samples are placed in the hole in 

the center and spun at ultra high speed. The probe mounts inside the bell-shaped 

magnetic field.

Sample holders that fit in the probe 

show only small amounts of material 

are required.

NMR

Solid-state

Central
10 INQUIRY Issue 2 • 2009 

The most recent addition to Ames 

Laboratory’s cadre of NMR specialists is 

associate physicist Yuji Furukawa, who 

joined the Materials Sciences and Engineering program earlier this year. Furukawa, who was on the faculty in the 

Department of Physics at the Hokkaido 

University, Japan, spent a year at Ames 

Lab roughly a decade ago as a visiting 

scientist working with physicist Fernando Borsa. When Borsa retired a year 

ago, Furukawa jumped at the chance to 

return to Ames.

“There’s an excellent research environment here,” Furukawa says. “The 

collaboration is very strong, much more 

so than in Japan. You work as a team.”

Furukawa is still in the process of 

setting up his research laboratory, awaitPruski, an Ames Laboratory senior scientist, and his group, which currently includes Ames Lab associate scientist Jerzy 

Wiench and graduate students Kanmi 

Mao and Stacey Althaus, have focused on 

the chemical and physical properties of 

materials involved in heterogeneous catalysis, surface science and materials science. The work on catalysts, done primarily in collaboration with Ames Lab senior 

chemist and Chemical and Biological Sciences Program director Victor Lin, focuses 

on studying the properties of surfaces, as 

well as the molecular structure, dynamics 

and reactions of the adsorbed species. 

Lin’s research involves mesoporous 

silica nanoparticles, sponge-like spheres 

only about 200 nanometers in diameter. 

They have thousands of parallel channels running through them. They can 

be filled with chemotherapy drugs and 

“capped” so they selectively release their 

payload only inside cancer cells. They 

can also carry thousands of particles of 

a catalyst, dramatically increasing the 

overall surface area of the catalyst over 

the same amount of catalyst produced 

in larger particles.

 “We’re working on characterizing the 

mesoporous silica nanoparticles, with 

the underlying motivation of designing them for various applications from 

nanocatalysts to algal oil harvest and 

drug delivery,” Pruski says. “We want 

to find out precisely what the surface 

structure is, which molecules attach, 

how they’re oriented and even what’s 

taking place during catalysis. Advancement in sensitivity and resolution of 

solid-state NMR techniques is essential 

to study these materials quickly and 

without isotope enrichment.” 

The group also has worked with 

Ames Lab senior scientist Vitalij Pecharing the installation of a dilution refrigerator that will allow him to study materials 

down to 0.05 Kelvin. He also has equipment that allows him to vary both temperature and magnetic field strength.

“When you study materials at extremely low temperatures, even small 

changes in temperature can sometimes 

lead to dramatic changes in properties,” 

Furukawa says.

He, along with many researchers in 

Ames Laboratory’s Materials Sciences and 

Engineering program, is involved in 

studying nanoscale molecular magnets 

and the new class of iron-arsenide superconducting materials. 

sky on characterization of novel materials for hydrogen storage, mainly complex 

metal hydrides synthesized by means of 

a solvent-free technique (mechanochemistry) or by chemical approaches (self-assembled micelles).

Probing Catalysts

Nanoscale Molecular 

Magnets and Superconductors

Marek Pruski

Yuji Furukawa
in a collagen matrix in a ratio of 40-to50 with the remaining 10 percent being 

water, which in part forms a monomolecular layer at the interfaces between 

phosphate and collagen, coupling the 

components of the composite like viscous glue. A relatively new research 

focus, pursued by Schmidt-Rohr and 

co-principal investigator Eugene Levin in 

collaboration with Ames Lab associate 

scientist Bruce Cook, is ternary and quaternary thermoelectric tellurides. 

“Tellurium has been considered an exotic isotope in NMR,” says Schmidt-Rohr, 

“but in fact there are many technologically interesting tellurium compounds. 

By elucidating the local structure and 

charge-carrier concentration, 125Te NMR 

can make important contributions to establishing structure-property relaxations 

in partially disordered tellurides.”

Schmidt-Rohr’s group is also involved 

in several other projects looking at the 

structure of natural organic matter from 

soil to biochar, a byproduct of gasification 

of biorenewable crops.

INQUIRY Issue 2 • 2009 11

Senior chemist Klaus Schmidt-Rohr’s 

group studies the composition and nanoscale structure as well as dynamics 

of polymer materials, nanocomposites, 

natural organic matter, and thermoelectric tellurides, using a variety of selective 

or two-dimensional NMR experiments, 

many of which they developed. 

One of the first was a study of Nafion®, a proton-exchange membrane 

widely used in fuel cells. Despite its popularity as a fuel-cell membrane, little was 

known about the molecular structure that 

separates water into its component parts 

of hydrogen and oxygen and at the same 

time releases electrons that generate 

power from the fuel cell. Through NMR 

and scattering studies, Schmidt-Rohr developed a model in which the polymer 

forms long, parallel water channels randomly dispersed throughout the material.

A variety of nanocomposites has 

also been studied by the group, including work on the loading-bearing nanocomposite found in bone. This material consists of 3-nanometer-thick apatite 

(calcium phosphate) platelets imbedded 

Polymers, Nanocomposites and Thermoelectrics

Schmidt-Rohr’s group is working on a 

variety of materials and techniques.

Klaus Schmidt-Rohr
12 INQUIRY Issue 

• 2009 

Source: Encyclopaedia Britannica, Inc.
INQUIRY Issue 2 • 2009 13

Ames Laboratory scientists investigate 

interaction of wind turbines and crops

Wind Power May Stir Up

IND TURBINES IN IOWA’S FARM FIELDS 

may be doing more than churning out 

electricity. As turbine blades turn to create 

“green” energy, they might also be helping 

green up surrounding crops. Scientists at 

Ames Laboratory are examining interactions between wind turbines and nearby plants to determine how wind farming might 

benefit corn and soybean farming.

The team, led by Ames Laboratory associate and agricultural 

meteorology expert Gene Takle, will focus on the extra air 

turbulence created by turbines. Takle and his colleagues suspect 

the turbulence may speed up natural exchange processes between crop plants and the lower atmosphere. 

For instance, crops warm up when the sun shines on them, 

and some of that heat is given off to the atmosphere. Extra air 

turbulence likely speeds up this heat exchange, so crops stay 

slightly cooler during hot days. On cold nights, turbulence stirs 

the lower atmosphere and keeps the nighttime temperatures 

around the crops warmer.

“In this case, we anticipate turbines’ effects are good in the 

spring and fall because they would keep the crop a little warmer and prevent a frost,” says Takle, who is also an Iowa State 

University professor of agronomy and of geological and atmospheric sciences. “Wind turbines could possibly ward off early 

fall frosts and extend the growing season.”

The research team also plans to examine turbines’ effects 

on moisture levels. Extra turbulence may help dry the dew on 

plants earlier in the morning, minimizing the amount of time 

fungi and toxins can grow on plant leaves. And drier crops at 

harvest help farmers avoid the cost of artificially drying corn or 

soybeans.

Plus, extra air turbulence could direct more carbon dioxide, 

a “fuel” for crops, down into the plant canopy or pump carbon 

dioxide up out of the soil, both of which are potentially helpful 

to photosynthesis.

Takle’s wind turbine predictions are based on years of research on agricultural shelter belts, or rows of trees in a field, 

designed to slow the wind. 

“In a simplistic sense, a wind turbine is nothing more than 

a tall tree with a well-pruned stem. For a starting point for this 

research, we adapted a computational fluid model that we use 

to understand trees,” says Takle. “But we plan to develop a new 

model specific to wind turbines as we gather more data.”

The team has started some initial measurements, including making visual observations of wind turbulence upwind and 

downwind of turbines and placing anemometers to determine 

turbulence intensity. But the bulk of the wind turbulence measurements and crop moisture, temperature and carbon dioxide 

measurements will begin in the spring.

“We anticipate the impact of wind turbines to be subtle, but in 

certain years and under certain circumstances the effects could 

be significant,” says Takle. “When you think about a summer with 

a string of 105-degree days, extra wind turbulence from wind 

turbines might be helpful. If turbines can bring the temperature 

down below 100 degrees that could be a big help for crops.”

Greener Crops

Gene Takle

BY BREEHAN GERLEMAN LUCCHESI

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For more information:

Gene Takle, (515) 294-9871

gstakle@iastate.edu 

Research funded by:

Ames Laboratory royalty income seed funding program

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14 INQUIRY Issue 2 • 2009 

UMMER VACATION CAN MEAN THE SAME FOR 

teachers as it does their students – time off to relax, vacation or pursue other interests. For eight 

hard working and committed middle school science 

teachers, pursuing other interests has led to 4-6 

weeks of additional time in the classroom and the research 

laboratory at the Ames Laboratory for each of 

the past three summers. The students spent 

four weeks the first year honing their teaching 

skills by working on content instruction with a 

Master Teacher. The second and third years of 

the program were spent conducting research 

projects under the guidance of Ames Laboratory scientist/mentors. 

The eight teachers were the inaugural group 

of participants in Ames Lab’s Academies Creating Teacher Scientists, or ACTS, program, a Department of Energy program designed to help 

teachers “progress as leaders of science, technology, engineering and mathematics, or STEM, 

education.” Summer 2009 marked the end of 

their three-year commitment at the Lab, and as 

part of their program wrap-up, all eight agreed 

to discuss how the ACTS experience has helped 

them become better teachers. 

Detailed, unique, fun and valuable were 

among the words thrown out by teachers to 

describe their ACTS experience. But two words — “revitalized” 

and “collaboration” — seemed to surface repeatedly. 

“I’ve been revitalized over the past three years,” says Kecia 

Goodman, an eighth-grade teacher at Ames Middle School in 

Ames, Iowa. “When I went back into the classroom last year, I 

had all these ideas, and I wanted to try every one of them and 

make everything work,” she says. 

“Science is much more collaborative than I ever thought,” 

says Sharon Andrews, a fifth-grade teacher from the Challenge 

Center in Sioux Falls, S.D. “In our little classrooms, we don’t get 

to collaborate with anybody, but that’s not what I experienced 

at Ames Lab where scientists talk to each other all the time. 

It would be so beneficial if we could do more of that in our 

classrooms.” 

Daniel Andrews, an eighth-grade teacher from Ames Middle 

School, agrees collaboration is important, but adds “dialogue” 

is the key “take home” he will bring back to his classroom. “If 

we can tap into the importance of ‘dialogue’ in our classrooms, 

that’s going to be really powerful,” says Andrews. 

In addition to classroom-instruction techniques and research 

experiences, throughout the three-year program, the ACTS 

teachers toured laboratories, took road trips to other DOE labs, 

and listened to science experts. 

“I can’t wait to get back and design some of my own labs using the inquiry techniques that I’ve learned here,” says Rayford 

S

What I Did on My Summer Vacation

BY STEVE KARSJEN

Middle school teachers make science their summer project

Sharon Andrews (right), Sioux Falls, S.D.
INQUIRY Issue 2 • 2009 15

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Sims, teacher at Maxfield Elementary School in St. Paul, Minn. 

“This program has filled a tremendous gap for me.” 

“As a result of ACTS, I’ve seen direct impacts on my students, 

adds Charlie Velasquez, fifth-grade teacher from Mulberry Elementary in Muscatine, Iowa. “I’ve had a record number of kids 

doing science fair, and the projects that we’ve done have been 

high-quality. This program has been very, very beneficial for me 

and my students.” 

“Simply put, I’ve gained more confidence as a teacher,” says 

Sharon Andrews, which is a fitting ending for the first-term ACTS 

teachers and the perfect beginning for the new set of teachers 

who’ve just begun the program in 2009.

Rayford Sims, St. Paul, Minn.

Daniel Andrews, Ames, Iowa

Charlie Velasquez, Muscatine, Iowa

Kecia Goodman, Ames, Iowa
2009ISSUE 2

Ames Laboratory

111 Technical and Administrative Services Facility

Ames, Iowa 50011-3020

515-294-9557

www.ameslab.gov