CHEMICAL ENGINEERING department of university of delaware

Research Cover 4.qxp
8/19/2003
9:00 AM
Page 2
CHEMICAL
ENGINEERING
university of delaware
research
report
www.che.udel.edu
department of
Research Cover 4.qxp
8/19/2003
9:00 AM
Page 3
Report from the Chair
O
n behalf of all who have contributed to this
outstanding Research Report, I welcome
you to our department! To those who are
old friends and alumni, I think that you will see in
these pages how the tradition of excellence in
Chemical Engineering at the University of Delaware
continues to flourish. It is reflected both in our core
strengths and in the expanding frontiers of our
department and our profession. To those for whom
this is the first introduction to the department, I
hope that the exciting and ever evolving activities
that you see here will entice you to find out more.
Open the newspaper or tune into your favorite cable
channel, and you probably won’t have to wait long to
find some distinguished social commentator offering a truism along the lines that "the only thing constant is change." Those nodding in agreement at
today’s dizzying pace might note that this idea can
be traced back at least as far as the Greek philosopher, Heraclitus, about 2500 years ago!
Nevertheless, as James Burke has pointed out in The
Day the Universe Changed, one thing that does distinguish modern society is the creation of organizations whose principal mission is to create
change–modern research institutions. These may be
industrial, governmental, or academic institutions.
What makes the last of these so attractive to many of
us is the fusion of the mandate to create and apply
knowledge with the traditional heritage of the university to transmit the knowledge of past generations to
present and future ones.
Even that description of the joys of academia does
not do justice to the integral role of research in the
process of education. Our students are truly partners in discovery. And not just our graduate students– more than half the members of each
undergraduate class in our department will have
conducted research and produced a thesis by their
graduation. Many will publish in science and engineering journals or present their findings at technical meetings, but even if they don’t, the individual
attention they receive from the faculty in these collaborative research endeavors is likely to be one of
the formative experiences of their educational
careers. Whatever subsequent career path or educational track our graduates follow, the experience
of exploring and extending the frontiers of the field
is one that stays with them.
What’s new in Chemical Engineering at the
University of Delaware? This Research Report will,
we hope, provide a snapshot. In the interval since
our last report, change has indeed been a constant. Five new faculty colleagues have joined us
since 2001, and we’re not done yet! They have
added to our existing strengths in areas such as
molecular thermodynamics, catalysis, colloids,
complex fluids, and control, and have brought new
thrusts in systems biology, electronic materials
processing, pharmaceutical engineering, and high
throughput experimentation into our research
portfolio and our teaching. With the creation of the
Delaware Biotechnology Institute, of formal connections to Thomas Jefferson University and its
medical school, and of significant multidisciplinary research funded by the COBRE program of
the National Institutes of Health and other
sources, the department’s emphasis on the biological sciences and engineering has accelerated.
In this report you will find a host of examples
where the perspectives and skills of chemical
engineers, from molecules to systems, are advancing biological frontiers. Projects ranging from the
control of protein folding processes, to metabolic
engineering, to protein separation and stabilization, to systems biology, to cellular mechanics, are
described in the pages that follow. There is little
doubt that the life sciences are an integral part of
21st century chemical engineering, and it will be
fascinating to watch how we develop these together in the years ahead. Stay tuned!
The impact of research innovations is even greater
when these stimulate educational innovations.
Continuous curriculum improvement is essential in
any academic department that values intellectual
vibrancy. We are in the process of implementing a
streamlined curriculum that will permit students in
chemical engineering to explore a broader range
of science and engineering disciplines at an
advanced level. In concert with this effort, we have
created a new minor in Biochemical Engineering,
which will be available to science and engineering
students across the campus. Many of our undergraduate students already pursue minors in chemistry, biology, and materials science (not to mention economics, music or languages), and we envision a future in which the broadening experience
gained through the pursuit of a minor will be the
normal experience for all of our majors. At the
same time we are working hard to incorporate the
latest advances, from the life sciences to computational tools, into our curricular offerings at all
levels, to guide students to forge intellectual connections between a broad range of experiences
inside and outside the classroom.
While change may be a constant, so are words on
a printed page. For the latest on the exciting initiatives, activities, and people in our department,
please visit our website at www.che.udel.edu.
Better yet, come see us in person!
Mark A. Barteau
Robert L. Pigford Professor and Chair
7258_chemengsingles cc.qxp
8/18/2003
3:37 PM
Page 1
Scanning confocal microscopy image of protein uptake into chromatographic particles
(see pg. 22)
Inside
front cover Structural representation of
4M5.3 single-cchain antibody
Dr. Anne Skaja Robinson
page 26
Message About Our Undergraduate Program
2
Graduate Study in Chemical Engineering
3
Centers Affiliated with Chemical Engineering
4
Equipment and Facilities
6
Research Areas
9
Faculty and Their Research
10
Funding
35
Staff
36
1
7258_chemengsingles cc.qxp
8/18/2003
3:37 PM
Page 2
Message About Our Undergraduate Program
T
his is an exciting time for undergraduate
education at the University of Delaware. Our
students are being hired by an everbroadening array of employers, including
companies in the biotechnology, semiconductor,
management consulting, and pharmaceutical
industries, in addition to a variety of small start-up
companies and the traditional chemical process
industry. The Accreditation Board for Engineering
and Technology (ABET) has developed an entirely
new set of educational criteria for chemical
engineering programs, establishing new and more
stringent requirements while at the same time
providing greater room for innovation in undergraduate education. We are using this flexibility to
prepare students for the increasingly multinational and ever-changing chemical and
pharmaceutical industries.
The department views these developments as
unique opportunities for strengthening chemical
engineering education. Our undergraduate
program is consistently ranked as one of the top
10 programs in the nation. Our goal is to provide
the best undergraduate education in chemical
engineering anywhere, with programs designed to
meet the challenges that our graduates will face
throughout their professional careers. One
sobering promise that we make to each
graduating class is that the new class of freshman
arriving in the fall will receive a better education
than they did. The challenge to our graduating
seniors is to embrace life-long learning to remain
at the top of their game; the challenge to our
faculty is to continuously improve our program so
that each generation of students is better
educated than the last. There is no such thing as
the status quo; there is no resting on our laurels,
however glorious or well-earned they may have
been.
A number of chemical engineering departments
around the country have renamed themselves in
recent years with titles such as "Chemical and
Bio-molecular Engineering." We have not done so
at the University of Delaware, but make no
mistake - our intent is to offer opportunities to
those interested in engineering and the life
sciences that are second to none. Students
entering in the fall of 2003 will be see a revised
and streamlined curriculum that incorporates
more biological applications in core chemical
engineering courses, and makes room for our new
minor in Biochemical Engineering. These changes
are being phased into the curriculum so that our
current students will reap some of their benefits,
2
and our current sophomores and juniors have
enthusiastically embraced the new minor, even in
advance of the streamlined curriculum meant to
accommodate it. We believe that the combination
of the Chemical Engineering major and the
Biochemical Engineering minor is the most
effective way to provide our students with an
education that incorporates cutting edge
applications of the life sciences, while maintaining
the value, both in terms of intellectual framework
and of "brand recognition" in the market place, of
Chemical Engineering.
In addition to the increased focus on biology and
biochemistry, the department continues to
strengthen the use of modern computational and
engineering tools. A major part of this effort is the
construction of state-of-the-art computer teaching
facilities that enable us to more effectively
introduce new software for numerical analysis,
process control, and process design/simulation.
The first of these opened in Colburn Lab in time for
the 2001-02 academic year, and the second will
be on line for the coming year. The department
also maintains its own computer laboratory,
accessible to our students 24/7. This facility is
undergoing a complete renovation and hardware
replacement this year as well.
While we are delighted to highlight the caliber of
our chemical engineering program, the
commitment to students across the University of
Delaware is an integral part of the outstanding
education that we provide. Recent recognition of
the University for its educational innovations has
come from sources such as the Carnegie
Foundation's Boyer Commission on undergraduate education at research universities, which
cited the University of Delaware as one of five
national leaders in providing active learning
experiences unavailable to undergraduates at
most research universities. The National Science
Foundation has also recognized UD as one of 10
institutions nationwide to exhibit "bold
leadership" and "meaningful results" in the
integration of research and education. Most
recently, the Reinvention Center, a national center
that focuses on undergraduate education at
research universities, named the University of
Delaware as the model for undergraduate
research and problem-based learning, and
recognized it along with only Princeton, Stanford
and Berkeley as exemplifying best practices in the
successful engagement of undergraduates at
research universities. Chemical Engineering at
Delaware truly is the best of the best!
7258_chemengsingles cc.qxp
8/18/2003
3:37 PM
Page 3
Graduate Study in Chemical Engineering
I
f you are considering graduate study, just
look through the pages that follow.
Graduate research in Chemical
Engineering reaches far beyond the topics
covered in undergraduate textbooks. From
metabolic engineering, to protein folding, to
nanotechnology, to colloids, to polymer
synthesis, to electronic materials, to
computational chemistry, to catalysis, to
process control, to the environment, the
range of challenging problems tackled by our
students is truly amazing. The size of our
faculty allows us to carry out research across
the frontiers of modern chemical
engineering, and to do so with considerable
depth. As a graduate student, you will
discover that the difficulty is not in finding a
project that excites you, but in choosing
among so many intriguing possibilities.
While Chemical Engineering at Delaware
has long ranked as one of the premier
departments in the country, one thing that
sets our department apart is a sense of
community. We graduate one of the largest
numbers of Chemical Engineering PhD’s
each year, yet the typical research group of
each faculty member numbers about 6
students. Graduate education and research
with a faculty mentor involves extensive
one-on-one interactions, and we believe
that it is essential to provide the level of
attention that our students' commitment to
advance studies deserves. At the same
time we come together frequently as a
community for both professional and social
events. Twice each year we hold a
departmental Research Review, a
symposium at which graduate students
give formal presentations about their
research. Each student presents twice at
these, once in their second year of graduate
study and once in the fourth year. The
second year talks, in particular, provide
excellent preparation for the sorts of
presentations that our students make at
local, regional, and national scientific
meetings throughout their careers. The
Research Reviews, along with many other
events throughout the year, are organized
and run by the COLBURN CLUB, our
departmental graduate student association.
Many of our graduate students take
advantage of the rich array of
interdepartmental and interdisciplinary
programs and resources to enhance the
breadth of their experience here. Examples
include many of the centers and programs
detailed in this report, such as the Center
for Composite Materials, the Center for
Catalytic Science and Technology, the
Center for Molecular and Engineering
Thermodynamics, the Institute for Energy
Conversion, the Delaware Biotechnology
Institute, the Chemistry and Biology
Interfaces Program, and the IGERT Program
in Biotechnology. These provide students
with access to facilities, faculty mentors,
and graduate student peers well beyond the
scope that any one department could offer,
and are crucial to our commitment to
provide educational and research
opportunities at the inter-disciplinary
frontiers of our field. In addition, students
benefit from many other formal and
informal collaborations, which often
generate opportunities to carry out
research at academic, industrial and
government laboratory sites, from local to
international venues.
Finally, one of the opportunities unique to
our department is our Teaching Fellows
Program. Each year we select 2 to 4 senior
graduate students to serve as teaching
fellows. These are chosen from our most
outstanding students whom we think have
what it takes to be faculty members. As
teaching fellows, they serve as coinstructors in one of our core courses under
the mentorship of an experienced faculty
member. The teaching fellow typically
delivers one third of the lectures, and
participates in all of the other activities of a
faculty instructor, from leading recitations
to writing and grading examinations. This
program provides outstanding opportunities
for our top students to experience teaching
"from the other side of the desk," whether
they choose to pursue an academic career
or not. Over the past decade, many of our
teaching fellows have gone on to faculty
positions across the U.S., and this program
has helped to make Delaware one of the
top producers of chemical engineering
faculty. Graduate study is about so much
more than research, and our aim is to
develop our students on many fronts.
Check us out!
3
7258_chemengsingles cc.qxp
8/18/2003
3:37 PM
Page 4
Centers Affiliated with Chemical Engineering
JINGGUANG G. CHEN
Director, Center for
Catalytic Science and
Technology
Professor of
Chemical Engineering
Ph.D. University of
Pittsburgh (1988)
B.S. Nanjing
University, China
(1982)
www.che.udel.
edu/ccst
Center for Catalytic Science and Technology (CCST)
I
t has been estimated that catalysis-based
processes represent 90% of current
chemical processes and generate 60% of
today's chemical products. Traditional roles
in these industries, catalysts are of growing
importance in fields ranging from environmental protection to pharmaceuticals and
processing high performance materials.
Recognizing the central role of catalysis in
industrial practice, the Center for Catalytic
Science and Technology (CCST) was founded
at the University of Delaware in 1978. The
Center has pioneered multi-disciplinary
research in the scientific and engineering
principles of catalysis. CCST’s research
programs involve faculty, students, and
postdoctoral fellows in the departments of
Chemical Engineering, Chemistry & Biochemistry, Materials Science & Engineering,
and Mechanical Engineering. In addition to
Professors Barteau, Buttrey, Chen,
Lauterbach, Lobo, Vlachos and Willis, whose
research is described elsewhere in this
report, faculty participants in the Center
include, from Materials Science and
Engineering, Ismat Shah (nanostructured
materials, thin films, and nanoparticles);
from Chemistry & Biochemistry, Douglas J.
Doren (computational chemistry), Klaus H.
Theopold (homogeneous catalysis, olefin
polymerization, selective oxidation), Andrew
V. Teplyakov (surface science of metals and
semiconductors); and from Mechanical
Engineering, Hai Wang (quantum and
statistical mechanical theories).
The hallmark of the Center's research
continues to be its strong connection to
industrial practice. These ties have been
forged through a number of mechanisms,
including the Center's Industrial Sponsors
Program, industrially supported grant and
contract research, collaborative projects with
industrial scientists and engineers, and
industrial sabbaticals and exchanges of
research personnel. CCST's laboratories and
wide range of research instrumentation
represent one of the foremost facilities for
catalysis research in academia.
STANLEY I. SANDLER
Director, Center for
Molecular and
Engineering
Thermodynamics
H. B. du Pont Chair of
Chemical
Engineering
Professor of
Chemistry
Ph.D. University of
Minnesota (1966)
B.S. City College,
New York (1962)
Delaware (1976)
www.che.udel.
edu/cmet
4
Center for Molecular and Engineering Thermodynamics (CMET)
T
he Center for Molecular and Engineering
Thermodynamics, was established in
1992 to advance research in both the
basic and applied areas of thermodynamics.
Thermodynamics is at the very heart of
chemical engineering practice. Most separations processes are based on thermodynamics and phase equilibria, and separations/purifications account for between 7090% of the energy and operating costs of
most chemical plants. There is now
considerable interest in thermodynamics
related to the purification of pharmaceuticals
and other biologic materials, a wide range of
environmental problems, nanotechnology,
and new separations technologies based on
membranes, supercritical extraction, and
micellar and surfactant solutions. In addition
to classical thermodynamic measurements,
new experimental methods, and a large
variety of computational chemistry
techniques that directly probe molecular
phenomena, have become an increasingly
important part of the Center research and
have expanded the role of molecular thermodynamics in chemical engineering research.
These methods are increasingly being
adopted in chemical engineering practice to
solve problems in the design of new processes and products, especially within the
context of stringent regulatory requirements
for environmental compat-ibility, and the
emergence of new industries for chemical
engineers. CMET's (4) Chemical Engineering
faculty members, Professors Stanley I.
Sandler, Director, Abraham M. Lenhoff,
Norman J. Wagner, Dean Eric W. Kaler,
Chemistry: Professor Doug Doren, Physics:
Professor Krzysztof Szalewicz and Chemistry
and Biochemistry: Professor Robert H. Wood,
bring together a wide range of theoretical,
computational and experimental capabilities
in thermodynamics, separation processes,
and simulations to address contemporary
processing, bioseparations, nanotechnology,
and environmental problems.
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 5
Centers Affiliated with Chemical Engineering
JOHN W. GILLESPIE, JR.
Center for Composite Materials (CCM)
F
ounded in 1974, the University of Delaware
Center for Composite Materials (UD-CCM) is
an internationally recognized interdisciplinary center for composites research,
education, and technology transfer. UD-CCM is
currently host to three (3) DoD Centers of
Excellence and is widely considered the top-ranked
academic research center in composites. UD-CCM
provides an intellectually stimulating research
environment for graduate studies that involves 7
departments and 3 colleges across campus and
more than 150 faculty, staff and students.
The UD-CCM’s Composites Manufacturing Science
Laboratory provides more than $7 million in stateof-the art equipment for polymer synthesis,
chemical, thermal and mechanical characterization,
sensors and processing of multifunctional
composite materials. UD-CCM also enjoys strong
support from industry with more than 30
companies in UD-CCM’s industrial consortium
seeking the next generation of scientists and
engineers and the latest technologies.
Examples of ongoing projects with Chemical
Engineering faculty include:
Eric Furst: Micromechanical spectroscopy for
nanoscale polymer structure and response.
Dionisios Vlachos : Fabrication and testing of
lightweight catalytic micropower generators.
Norman Wagner: Effects of shear thickening fluids
for use in polymer-matrix materials.
Richard Wool: Use of soy oil and natural materials
to make affordable fiber-reinforced composite
materials for high volume commercial applications.
Director, Center for
Composite Materials
Professor of Civil and
Environmental
Engineering
Professor of Materials
Science and
Engineering
Ph.D. University of
Delaware (1985)
M.S. University of
Delaware (1978)
B.S. University of
Delaware (1976)
Email us at [email protected] to request a copy
of our annual report or refer to our website. The
report includes posters of more than 90 ongoing
projects.
www.ccm.
udel.edu
DAVID S. WEIR
Delaware Biotechnology Institute (DBI)
A
n important component in Delaware’s
commitment to life sciences is the
Delaware Biotechnology Institute (DBI) at
the University of Delaware, a multidisciplinary, state
of the art center engaged in life science research,
education and economic development. The Institute
represents a $120M partnership among the State’s
academic institutions, the State of Delaware, and
representatives of the private sector.
Founded in 1999, DBI brings together researchers
in chemical engineering, chemistry, biochemistry,
biology, computer science, engineering and
materials science to research questions with
applications in agriculture, human health,
computational biology, protein structure and
function, marine ecosystems and biomaterial
systems.
DBI’s 72,000 ft2 facility is designed to house 170
researchers, and includes 23 individual
laboratories, 15 common labs and six core
instrumentation centers, including bioimaging,
microarray and functional genomics, protein
production, and bioinformatics. The Institute
merges industry experience and academic expertise
to facilitate the highest levels of research by an
effective complement of academic research labs
and start-up life science companies.
Located in the Delaware Technology Park adjacent
to the University of Delaware campus, the Institute
serves as a bridge linking academia and the public
and private sectors, facilitating education and
industrial internships for students, and attracting
and supporting new life science businesses as a
source of high-quality jobs in Delaware.
Director, Delaware
Biotechnology
Institute
Ph.D. University of
Glasgow, Scotland
(1958)
ARCST University of
Strathclyde, Scotland
(1955)
B.S. University of
Glasgow, Scotland
(1955)
www.dbi.
udel.edu
5
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 6
Equipment and Facilities
Biochemical Engineering Laboratory
T
his laboratory has facilities for recombinant
DNA research, protein purification, largescale cell growth, and array analysis.
Protein production facilities at the Delaware
Biotechnology Institute enable growth of cells up
to 40L and subsequent protein purification.
Analytical facilities include a spectrofluorimeter,
spectrophotometers, imaging equipment, and
liquid chromatography. Other standard equipment
includes an autoclave, laminar flow hoods,
incubators, controlled environmental shakers,
centrifuges and microscopes and a scintillation
counter.
Center for Catalytic Science &
Technology Laboratories
A
variety of catalyst synthesis,
characterization and reactor facilities
are housed in the Center. Among these
are flow and batch reactor systems for operation at
pressures ranging from a few Torr to 5000 psi.
These reactors are interfaced with GC, MS, or
GC/MS instruments for online product analysis.
Also available are Fourier transform infrared
spectrometers capable of obtaining spectral data
from the far-infrared region to the near-infrared
region (5000 to 20 cm-1). The spectrometers are
used in a wide range of catalytic applications,
including in situ high-pressure and hightemperature characterization of functioning
catalysts. In addition, two ReactIR instruments are
set up for studying reaction mechanisms and
kinetics. These are capable of real-time, in situ or
on-line analysis of chemical reactions and can be
utilized for elevated pressure measurements using
an Autoclave Engineering EZE-Seal reactor with
built-in infrared probe. Four scanning probe microscopes with collective capability for air, liquid or
vacuum operation provide real space imaging of
the atomic structure of surfaces by STM and AFM.
These instruments facilitate study of the relation of
the structure of modern catalytic materials to their
surface reactivity. A number of ultra high vacuum
surface analysis instruments are housed in the
Center. These instruments are all equipped for
multiple electron spectroscopic techniques for
determining surface composition, surface
6
structure, and surface reaction chemistry.
Available techniques include Auger Electron
Spectroscopy (AES), Low Energy Electron
Diffraction (LEED), mass spectrometry, X-ray and
Ultraviolet Photoelectron Spectroscopies (XPS and
UPS), Ion Scattering Spectroscopy (ISS), and the
High Resolution Electron Energy Loss Spectroscopy
(HREELS) and Scanning Auger spectroscopy. These
computer-controlled spectrometers all possess
equipment for cleaning sample surfaces, and for
carrying out surface reactions in the vacuum
environment. Two NMR spectrometers with
capabilities for analysis of solid samples are
housed in the Chemistry Department, and are used
to study the properties of catalyst surfaces. One
instrument operates at low field and can probe
carbon-containing reactants, surface
intermediates, and products. The second
instrument operates at 300 MHz and can probe
heavier nuclei such as silicon and aluminum in the
catalysts under investigation. Several Silicon
Graphics Solid Impact R10000 workstations (195
MHz, 64 bit microprocessor) and a Silicon
Graphics Indigo XZ R4400 (150 MHz and 32 bit
microprocessor) are part of the CCST
computational facilities. Modeling suite Cerius and
Insight II have been installed on these
workstations for molecular mechanics and
quantum chemical calculations, Rietveld
refinement of powder diffraction data,
transmission electron microscopy simulations, etc.
Finally, the Center faculty and students also have
access to several synchrotron beamlines at
Brookhaven National Laboratory.
Center for Molecular Engineering &
Thermodynamics Laboratories
T
he laboratories in the Center for Molecular
and Engineering Thermodynamics contains
equipment for the measurement of: low
pressure vaporliquid equilibrium, high pressure
vapor-liquid equilibrium, liquid-liquid equilibrium,
adsorption equilibrium, high pressure phase
equilibria, and transport properties at elevated
pressures.
Additional facilities for the study of surfactant
aggregates and phase behavior include: colloidal
characterization, microstructure characterization,
and phase observations.
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 7
Equipment and Facilities
Computational capabilities are also available
including: two Beowulf clusters, of 18 and 38
nodes, for parallel processing, Sun, Silicon
Graphics, and RISC workstations and access to
NSF-funded sites, computer software developed or
used by Center faculty to include molecular
dynamics and Monte Carlo codes, molecular
orbital calculations, and programs for phase
equilibrium calculations based on equations of
state and activity coefficient models. There are
also programs for the study of colloids and
proteins, for the direct analysis of experimental
data, and for chromatographic and other
separations processes.
Computational Facilities for Fluid
Dynamics/Nonequilibrium
Thermodynamics
S
tate-of-the-art facilities are also available for
commmunication-intensive large scale
computations in the area of Computational
Fluid Dynamics/Nonequilibrium Thermodynamics. The
facilities include a Linux Beowulf Cluster consisting of
24 Dual 2 Athlon MP 2000+ processors compute
nodes, each with 1.5GB RAM, and 30 GB storage, 1
head node, involving a Dual 2 Athlon MP 2000+
processors, 4.0GB RAM, and 430 GB RAID storage,
adding to a total compute capability of 50 processors.
The heart of the system is a Myrinet Interconnect
allowing the head and each one of the compute nodes
for simultaneous data transfers of 2Gbytes sustained
rates. In addition, a file server node offers 1.3 TByte of
RAID storage and an additional 0.8 TByte of backup
harddrive storage. All these facilities allow the
execution of large scale fluid dynamics parallel
computing simulations (using MPI) of up to 20 GFlops
sustained performance, thus enabling the
investigation of three-dimensional and time
dependent flow problems involving complex fluids,
requiring the time integration over hundreds of
thousands of time steps of millions of variables, such
as encountered in the investigation of polymerinduced drag reduction in turbulent flows.
Electron Imaging Facility
O
ur Electron Imaging Facility includes
two transmission electron microscopes
(TEMs) and three scanning electron
microscopes (SEMs). One of the TEMs is a 200keV
field emission high-resolution TEM (JEOL 2010F
FasTEM), made possible by generous support from
the W. M. Keck Foundation in 1999. It provides
ultra-high resolution (0.19 nm point resolution
with an information limit of 0.13 nm) coupled with
a wide range of analytical capabilities. This
instrument also provides remote-control capability
via the "FasTEM" package that couples digital
control with an internet-ready interface system of
hardware and software available for use in
collaborative efforts with our off-site partners.
High-resolution image contrast with the 2010F
directly represents the atomic structure of the
material. Peripheral features on this microscope
include EDAX Energy Dispersive Spectroscopy
(EDS), Parallel Electron Energy Loss Spectroscopy
(PEELS), a Gatan Image Filter (GIF), and a
scanning attachment (STEM). The STEM
capabilities on the 2010F allow for nanobeam
operation and consist of both bright field (on-axis)
and high-angle annular dark field (HAADF)
detectors, providing a powerful tool for producing
enhanced Z-contrast images. Software available
on the 2010F allows users to digitally capture and
process TEM and STEM images, generate
elemental maps, and construct ternary phase
diagrams. The second TEM is a 200 keV analytical
TEM (JEOL JSM-2000FX). This TEM is used
applications requiring high tilt angles for the
specimens as well as for many of the lessdemanding imaging and elemental analysis
studies. It is also used for training of new TEM
users. A number of specialized specimen holders
are provided with both TEMs, including cryogenic
holders for transferring and working with frozen
sections from soft materials.
Our SEM instruments are: (i) a new JEOL JSM7400F field emission SEM (ii) a JEOL 5300LV low
vacuum SEM, and (iii) a JEOL 840 SEM. The 7400F
purchase was made possible by generous support
from the NSF-MRI program. It is the latest stateof-the-art high-resolution SEM from JEOL,
featuring 1.0 nm resolution at 15 kV and operation
at accelerating potentials down to 0.10 kV. The
7400F has a secondary electron detector
complimented with an in-lens backscattered
electron detector to provide Z-contrast enhanced
images. Like the 2010F, the 7400F is also set up
7
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 8
Equipment and Facilities
for remote access and operation, providing off-site
collaborators with the opportunity to participate in
joint efforts via "telepresence." The 7400F and
840 models are each equipped with new Oxford
Instruments INCA EDS systems with high area (30
mm2) detectors and extensive INCA software
packages for mapping and analysis. The 5300LV
allows for operation at specimen environment
pressures up to about 2 torr, which is very useful
with specimens containing soft materials.
Polymer Physics Laboratory
T
his laboratory includes modern Rheometrics
and Instron equipment for measuring the
rheological properties of polymer melts and
solutions; rheo-optical equipment including flow
dichroism and birefringence and dielectric
spectrometers to characterize the electrical
properties of polymers. The laboratory includes
equipment for the preparation of polymer blends
and composites, as well as evaluation of their
mechanical properties.
Rheology & Polymer, Colloid, &
Surfactant Science Laboratories
T
his set of interdisciplinary laboratories in
Colburn Laboratory enables macroscopic to
molecular interrogation of complex fluids
and polymer melts and solids. Equipment funding
from the National Science Foundation and industry
has enabled construction of one of the largest
rheological sciences laboratories of its kind, with
research instruments spanning fundamental
rotational rheometry, capillary rheometry, and
bench-scale processing rheometry. Instruments
from Rheometric Scientific, Bohlin, Instron, Haake,
Paar Physica, and other manufacturers provide a
campus-wide user facility in support of rheological
sciences. Additional facilities enable extensive
rheo-optical investigations (flow birefringence and
dichroism) as well as simultaneous flow light
scattering and rheometry for mesoscale and
molecular investigations of materials under flow.
In conjunction with the National Institute of
Standards and Technology (NIST) we have
complementary flow-small angle neutron
scattering (Flow-SANS) capabilities for studies of
flow induced microstructure in complex fluids.
8
Additional facilities for dynamic mechanical
analysis, thermal dielectric spectroscopy and
rheology, electro-rheology, differential thermal
rheology, and high pressure rheology enable wideranging investigations into material properties and
microstructure development under processing.
Additional laboratories exist for fundamental
characterization of complex fluids and polymers in
solution. Instruments for dynamic and static light
scattering and fiber optic quasi-elastic light
scattering, phase analysis electrophoresis, and
capillary viscometry enable characterization of
molecular architecture, molecular weight, particle
size, particle shape, particle polydispersity and
thermodynamic properties of colloid and polymer
solutions. Instruments have been developed for
the detection of shear aggregation and dispersion.
Page 9
3:36 PM
8/18/2003
7258_chemengsingles cc.qxp
Research Matrix
The research matrix below summarizes each faculty member’s areas of expertise.
d
har
Ric
ol,
an
Wo
Bri
lis,
Wil man
or
r, N ios
gne
s
Wa Dioni
s,
te
c ho A n n e t
Vla
ne, nley
Shi
ta
r, S er
dle
s
San W. Fra
.
ne
l, T
sel
, An
Rus inson er
h
Rob
t op
hris
s, C tunde
er t
a
Rob , Bab aul
e
aik
o, R
unn
Lob am
Og
h
bra
f, A
n
hof J o c h e
Len
,
ach Eric
terb
er,
Lau
Kal ric
E
st,
Fur my
ere
s, J
ard
sad
Edw ti, Pra
el
urja
os t
Dh
n , C ng
a
nso
De inggu
n, J
las
C he
oug
y
y, D
ttre Anton
Bu
is,
Ber , Mark
au
r te
Ba
9
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 10
Faculty
MARK A. BARTEAU
Robert L. Pigford
Professor
Chair, Department of
Chemical Engineering
Professor of
Chemistry
Ph.D. Stanford
University, (1981)
Surface science and
catalysis on metals
and metal oxides,
spectroscopic
characterization of
surfaces and
catalysts.
M.S. Stanford
University (1977)
B.S. Washington
University (1976)
The objective of our research is the design of new
catalysts from first principles. By combining
powerful spectroscopic tools and surface reaction
studies on model catalysts with theoretical results
from computational chemistry methods, one can
obtain an unprecedented level of understanding of
catalytic intermediates, reaction mechanisms and
kinetics. These provide guiding principles for
catalyst design at the molecular level, and we are
devoting considerable effort to the synthesis and
evaluation of new catalytic materials. We are
particularly interested in chemical processes for
which selectivity to the desired product is the driving
consideration for catalyst improvement, often for
economic and environmental reasons. Our goal is to
understand the basis for catalyst selectivity at the
molecular level, and to use this knowledge for the
rational design of new and improved catalysts.
Reaction engineering principles also come into play;
heat and mass transfer and reactor configuration
must be considered. We have found that monolith
reactors operated in a short contact time mode
provide a flexible platform for testing our catalyst
design concepts.
NEW INTERMEDIATES & NEW CATALYSTS IN SELECTIVE
OLEFIN EPOXIDATION
SELECTED PUBLICATIONS
"Control of Ethylene Epoxidation Selectivity by
Surface Oxametallacycles," with S. Linic, Journal of
the American Chemical Society 125, 4034 (2003).
"New Perspectives on Direct Heterogeneous Olefin
Epoxidation," Topics in Catalysis, 22, 1 (2003).
"A Comparison of Gold and Molybdenum
Nanoparticles on TiO2(110) 1x2 Reconstructed
Single Crystal Surfaces," with J.R. Kitchin and J.G.
Chen, Surface Science 526, 323 (2003).
“Surface Chemistry and Catalysis on Well-defined
Oxide Surfaces: Nanoscale Design Bases for
Single-Site Heterogeneous Catalysts," with J.E.
Lyons and I.K. Song, Journal of Catalysis 216, 236
(2003).
"Principles of Reactivity from Studies of Organic
Reactions on Model Oxide Surfaces," with A. B.
Sherrill, in The Chemical Physics of Solid Surfaces, 9, D. P.
Woodruff (ed), Elsevier, Amsterdam p. 409 (2001).
10
The selective reaction of ethylene with oxygen to
manufacture ethylene oxide with silver catalysts is
one of the most important selective hydrocarbon
oxidation processes in commercial practice. There
is considerable interest in extending this process
to other olefins (e.g. propylene), but low reaction
selectivities remain a significant hurdle. By
combining Density Functional Theory calculations
with surface spectroscopic studies, we
demonstrated the first examples of a previously
unknown class of surface intermediates, called
oxametallacycles. These are cyclic species bound
to surface metal atoms via both their oxygen and
carbon atoms. We demonstrated for the first time
that these intermediates react to form epoxide
products. By using theory and experiment, we were
able to construct a comprehensive reaction
coordinate and microkinetic model for ethylene
epoxidation on silver, and to make quantitative
predictions about reaction kinetics and selectivity.
This work has led to the prediction and realization
of new bimetallic catalysts for ethylene
epoxidation. These would not have been possible
without the molecular level understanding of
surface reaction mechanisms, reaction
intermediates, and even transition states made
possible by the coherent application of surface
science experiments and theory.
NEW METAL OXIDE CATALYSTS FROM UNDERSTANDING
SURFACE SITES
We use a variety of surface science techniques
such as Temperature Programmed Desorption
(TPD), X-ray Photoelectron Spectroscopy (XPS),
Scanning Tunneling Microscopy (STM) and Near
Edge X-ray Absorption Fine Structure (NEXAFS) to
identify surface intermediates and to probe the
nature of surface sites. We have discovered a
number of reactions that occur at surface sites
which meet specific coordination and oxidation
state requirements. These discoveries provide
excellent opportunities to invent new catalytic
processes, such as our patented process for the
environmentally benign synthesis of ketenes. The
combination of surface science and catalytic
reactor experiments is providing important
information about selectivity control and
mechanisms of catalyst deactivation. Additional
thrusts include surface science studies of oxidesupported metal catalysts, and dynamic
microbalance studies of redox processes on
working oxide catalysts.
FROM SINGLE MOLECULE SPECTROSCOPY TO
SUPPORTED MOLECULAR CATALYSTS
We are exploring the assembly of new selective
oxidation catalysts by molecular functionalization
of surfaces with ordered arrays of discrete, reactive
oxide molecules. Heteropolyanions
(polyoxometalates) such as H3PMo12O40 can be
deposited to from ordered monolayers that permit
site-by-site mapping of chemical functions on the
surface, as well as characterization of redox
properties of individual molecules by tunneling
spectroscopy with the scanning tunneling
microscope. These nanoscale oxide clusters exhibit
Negative Differential Resistance in their tunneling
spectra at potentials that track their reduction
potentials. Thus tunneling spectroscopy
measurements provide correlation and prediction
tools for catalyst performance in selective oxidation
processes. Because polyoxometalate monolayers
present uniform catalytic sites whose redox
properties can be defined by single molecule
spectroscopy, they may serve as a prototype of
single site heterogeneous catalysts designed and
fabricated on the nanoscale.
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 12
Faculty
DOUGLAS J. BUTTREY
Associate Professor
of Chemical
Engineering
Ph.D Purdue
University (1984)
M.S. Purdue
University (1978)
B.S. Wayne State
University (1976)
Synthesis and
characterization of
functional complex
oxides
SELECTED PUBLICATIONS
“Structural Characterization of the Orthorhombic
Phase M2 in the MoVNbTeO Propane Ammoxidation
Catalyst,” with P. DeSanto, R.K. Grasselli, C.G.
Lugmair, A.F. Volpe, B.H. Toby, and T. Vogt, Topics in
Catalysis 23, 23 (2003).
“Multifunctionality of Active Centers in (Amm)
oxidation Catalysts: from Bi-Mo-Ox to Mo-V-(Te,Sb)Ox,” with R.K. Grasselli, J.D. Burrington, P. DeSanto,
C.G. Lugmair, A.F. Volpe, T. Weingand, Topics in Catalysis
23, 5 (2003).
“Mid-infrared Conductivity from Mid-gap States
Associated with Charge Stripes,” with C.C. Homes,
J.M. Tranquada, Q. Li and A.R. Moodenbaugh, Phys.
Rev B 67 (18), 184516 (2003).
"Transmission Electron Microscopy Study of ChargeStripe Order in La1.725Sr0.275NiO4," with J. Li, Y. Zhu,
J. M. Tranquada and K. Yamada, Phys. Rev. B, 67,
012404 (2003).
“Freezing of a Stripe Liquid,” with S.-H. Lee, J. M.
Tranquada, K. Yamada and S.-W. Cheong, Phys. Rev.
Lett. 88 (12), 126401 (2002).
12
COMPLEX OXIDE OXIDATION CATALYSTS
Our research effort involves the study of relationships
between composition, structure, and physical
properties of complex oxides with the ultimate goal of
producing new technologically useful materials by
design.
Complex oxides, those comprised of multiple
metals, play an important role in oxidation
catalysis. Chemical complexity in crystalline
structures can lead to multifunctional combinations
of sites that are geometrically linked, redox
active, and isolated from equivalent
neighboring clusters. An
example,
Mo7.5V1.5NbTeO28, is
a new ammoxidation
catalyst that, in
combination with a
related oxide phase,
exhibits 63% yield for
conversion of propane to
acrylonitrile (AN). Annual
production of AN is about
1kg for every person on
earth for use in ABS plastics and synthetic fibers.
We have solved the crystal structure of this material
using a combination of electron microscopy with Xray and neutron diffraction. Based on this structure,
we have proposed a model for the catalytic
mechanism and are studying chemical variations
that may lead to improved performance through
design.
CORRELATED ELECTRON MATERIALS
New functional oxides based on electronic
correlations offer great promise for applications
involving high-temperature superconductivity,
ferromagnetism, and colossal magnetoresistance
(for magnetic storage). These oxides often involve
complex phase behavior, exhibiting extreme
variations in oxygen stoichiometry, solid-solid
phase separations, phase separation of charge
carriers and metal (or superconductor) - insulator
transitions. Controlling phase equilibria to produce
desired properties is a central theme of our
research in this area. Much of our work focuses on
the model system: (Ln,Sr)2NiO4+d, where Ln is a
lanthanide element and d indicates oxygen
nonstoichiometry. Strong interactions between
electrons in these systems lead to liquid, liquidcrystal or crystalline ordering of the charge carriers,
resulting in startling effects on physical properties
of these novel phases.
HIGH DIELECTRIC CONSTANT OXIDES
A new area of research for us involves the study of
two seemingly unrelated families of nanocrystalline
transition metal oxides: (Li,Ti)-doped NiO and
ΑCu3Ti4O12 with Α = Ca, Cd produced through solgel chemistry. These nanomaterials exhibit
exceptionally high dielectric constants with
ε ≈ 100,000. We have recently used transmission
electron microscopy to show the existence of
nanodomains (about 10 nm diameter) that we
believe are semiconducting, but separated by
insulating atomic-level boundaries in both
families. It may be possible to use such
materials as nanoscale capacitors and
memory devices.
7258_chemengsingles cc.qxp
8/18/2003
3:36 PM
Page 11
Faculty
Our research is concerned with the modeling and
simulation of the interplay of flow processes and
nonequilibrium thermodynamics in systems with a
complex internal microstructure, where multliple
scales of length and time are important. Typical
examples include the study of polymer and
surfactant-induced turbulent drag reduction, the
stress induced crystallization in fiber spinning,
free-surface flows with surfactants, etc. Our
primary concern is the interrelationship between
the flow and the microstructure. Our approach in
dealing with complex dynamic phenomena
involving multiple scales in length and time is
hierarchical. Our theoretical analysis starts from
non-equilibrium thermodynamics considerations
of the microstructure which is obtained by
modifying and extending in a thermodynamically
consistent fashion models in the literature or
generated directly from microscopic nonequilibrium Monte-Carlo simulations, as needed.
Then, based on our own modeling approach (see
research monograph in the references below), this
microscopic information is linked to a thermodynamically consistent macroscopic continuum
description. Last, but not least, specific
predictions on particular processes are calculated
through the use of state-of-the-art computational
facilities (parallel supercomputers) and the results
are compared against experiments and evaluated
using tools from nonlinear analysis (i.e., stability
analysis and bifurcation theory).
VISCOELASTIC EFFECTS ON FLOW INSTABILITIES &
SECONDARY FLOWS
Viscoelastic instabilities are often the limiting
factor determining the maximum throughput in
polymer processes, such as extrusion. In many
occasions coupling of the flow with other
transport phenomena, like chain migration, or
taking into account surface interactions, can play
a critical effect - see references. Moreover, the
onset of secondary flows and the flow patterns
resulting from it constitute a sensitive test for
models for the stress and macromolecular
conformation in highly elastic polymer solutions
and melts. Three-dimensional and/or timedependent secondary flows are much more
common with viscoelastic than Newtonian flows
necessitating large scale computations. One goal
is to predict the substantial increase in pressure
drop observed when secondary flows, set-in as
the elasticity of the flow increases in a variety of
flows, such as, flow around objects, flow through
porous media, etc. For the theoretical
investigation of these phenomena, we use
computer-aided nonlinear analysis and 3D and
time-dependent direct numerical simulations
implemented on parallel supercomputers.
ANTONY N. BERIS
POLYMER-INDUCED DRAG REDUCTION
Albeit drag reduction has been known since the
pioneering work by Tomms in the 40s, and albeit
a substantial experimental work has since then
been accomplished, it is only recently (following
our earlier work-see reference) that theoretical
investigations have been made possible on a
routine basis starting from independently
evaluated models. This has been made possible
due to the development of efficient and stable
numerical algorithms based on spectral
approximations and the advent of powerful
parallel computers. In our previous work we have
demonstrated the key role played by an enhanced
extensional viscosity in delaying the development
of the eddies that feed the turbulence, thus
substantiating a mechanism for drag reduction
first recognized by Metzner and Lumley. We
continue this work, through the use of Direct
Numerical Simulations (DNS) of the turbulent
channel flow of a dilute viscoelastic polymer
solution, for a variety of models and under
different conditions and for different flow
geometries, in order to further elucidate the
details of this mechanism. Moreover, we are
interested to use DNS in developing models for
viscoelastic turbulence.
Arthur B. Metzner
Professor of
Chemical Engineering
Ph.D. Massachusetts
Institute of
Technology (1985)
B.S. National
Technical University
of Athens (1980)
Modeling and simulation
of complex flows,
nonequilibrium
thermodynamics and
transport phenomena,
with applications to
polymer turbulence, drag
reduction, stress-induced
polymer crystallization
MODELING OF THE STRESS-INDUCED CRYSTALLIZATION
IN FIBER SPINNING
The objective of this research effort is the
investigation of the flow-induced crystallization
and molecular orientation in the spinning of high
strength polymer fibers. A thermodynamically
consistent macroscopic model of the flow is to be
developed based on a detailed consideration of
the microstructure involving not only the
molecular amorphous chain orientation and
degree of crystallinity but also the crystalline
morphology. That necessitates a quantitative
description of the flow-influenced nonequilibrium polymer thermodynamics. This task is
currently under way through the use of detailed apriori lattice models of the polymer chains
conformations in the dense amorphous polymer
phase in semicrystalline polymers. New efficient
methods are used (see reference) that allow the
extraction of quantitative information without the
need for simplifying assumptions.
SELECTED PUBLICATIONS
"Direct Numerical Simulation of Polymer-induced
Drag Reduction in Turbulent Channel Flow," with R.
Sureshkumar and R.A. Handler, Physics of Fluids, 9,
743-755 (1997).
“A Hierarchical Model for Surface Effects on Chain
Conformation and Rheology of Polymer Solutions.
I. General Formulation,” with V.G. Mavrantzas, J.
Chem. Phys. 110, 616-627 (1999).
"Lattice-based Simulations of Chain
Conformations in Semi-crystalline Polymers with
Application to Flow-induced Crystallization," with
J.A. Kulkarni, J. Non-Newtonian Fluid Mechanics, 82, 331366 (1999).
“Stress Gradient-induced Migration Effects in the
Taylor-Couette Flow of a Dilute Polymer Solution,”
with M.V. Apostolakis and V.G. Mavrantzas, J. NonNewtonian Fluid Mechanics, 102, 409-445 (2002).
“Simple Non-Equilibrium Thermodynamics
Applications to Polymer Rheology” Rheology
Reviews 2003, D.M. Binding and K. Walters (ed.),
The British Society of Rheology, (2003).
11
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 13
Faculty
The main goal of our research is to identify novel
catalytic materials for applications in fuel cells,
selective removal of environmental pollutants,
photocatalysis, and gas sensors. Our research
approaches combine fundamental studies on single
crystal model surfaces with catalytic evaluations of
supported catalysts.
CARBIDES AS ALTERNATIVE FUEL CELL ELECTROCATALYSTS
Currently the leading electrocatalysts for hydrogen
and methanol fuel cells are Pt-group metals
(PGM). However, PGM materials are
disadvantageous in terms of their prohibitively high
costs and their susceptibility to be poisoned by
carbon monoxide (CO). Therefore, the discovery of
less expensive and more CO-tolerant alternatives
to the PGM electrocatalysts would greatly facilitate
the commercialization of hydrogen and methanol
fuel cells. In the past few years our group has
focused on the application of tungsten carbides as
potential alternatives to PGM. Our surface science
results indicate that tungsten carbides are active
toward the dissociation of hydrogen and methanol,
and are more CO-tolerant than PGM. We are
currently extending the promising surface science
results to electrochemical testing under realistic
fuel cell conditions.
JINGGUANG G. CHEN
NOVEL PROPERTIES OF NANOCATALYSTS
It is well known that materials often demonstrate
novel physical and chemical properties when their
sizes are reduced to nanometer scale. We have
several projects aimed at the understanding of
nanocatalytic materials. These include the
utilization of nano-carbides for the removal of nitric
oxides, nano-TiO2 for photocatalysis, and nanoPGM for chemical sensor applications. We are also
utilizing several advanced spectroscopies to
unravel the fundamental relationship between the
electronic structures and the physical dimensions
of nanoparticles.
Professor of
Chemical Engineering
Director, Center for
Catalytic Science and
Technology (CCST)
Ph.D., University of
Pittsburgh (1988)
B.S., Nanjing
University, China
(1982)
Surfaces and
interfaces,
nanostructured
devices and sensors,
environmental
catalysis.
BIMETALLIC CATALYSTS FOR LOW-TEMPERATURE
HYDROGENATION
Low-temperature hydrogenation can result in
selective removal of environmental pollutants from
chemical or petroleum feedstreams. It also offers
an opportunity to selectively hydrogenate desired
functional groups for pharmaceutical and chemical
applications. Our group has recently discovered
that alloying two metals, such as Pt and Ni, led to
hydrogenation at temperatures significantly below
those on either parent metal alone. We are
currently combining surface science, theoretical
modeling, and heterogeneous catalysis to search
for other bimetallic systems with enhanced
selectivity and activity for low-temperature
hydrogenation.
SELECTED PUBLICATIONS
“Potential Application of Tungsten Carbide as
Electrocatalysts: III. Reactions of Methanol and
Water over Pt-Modified C/W(111),” with N. Liu, K.
Kourtakis and J.C. Figueroa, Journal of Catalysis, 215 ,
254-263 (2003).
“Potential Application of Tungsten Carbide as
Electrocatalysts: IV. Reactions of Methanol and
Water on Closed-Packed Carbide Surfaces,” with
H.H. Hwu, Journal of Physical Chemistry B, 107, 2029-2039
(2003).
“A Comparison of Gold and Molybdenum
Nanoparticles on TiO2(110) 1x2 Reconstructed
Single Crystal Surfaces,” with J. R. Kitchin and M.A.
Barteau, Surface Science, 526 , 323-331 (2003).
“Correlating Mechanical Strain with LowTemperature Hydrogenation Activity on Ni/W(110),”
with N.A. Khan, Journal of Physical Chemistry B, 107, 43344341 (2003).
“Reactions of Methanol and Water on Carbide and
Oxycarbide-Modified Mo(110),” with H.H. Hwu, Surface
Science 536 , 75-87 (2003).
13
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 14
Faculty
COSTEL D. DENSON
Professor of
Chemical Engneering
Ph.D., University of
Utah (1965)
M.S., Rensselaer
Polytechnic Institute
(1960)
B.S., Lehigh University
(1956)
Polymer processing
and rheology, mixing,
mass transfer,
chemical reactions.
Polymer processing operations can arbitrarily be
divided into two rather broad categories which,
simply stated, are those operations concerned with
shaping polymeric materials into well-defined, enduse configurations and those operations not
concerned with shaping. Profile extrusion,
pultrusion, injection molding, tubular film blowing,
blow molding, and fiber spinning are examples of
polymer processing operations, which involve
shaping. Polymer processing operations, which do
not involve shaping, are most often conducted
upstream from shaping operations, and include the
following: vapor-liquid stripping operations when the
liquid phase is a molten polymer or polymer solution
(devolatilization), liquid-liquid stripping operations
where one liquid is a molten polymer or polymeric
solution, gas absorption in molten polymers,
polymerization and grafting reactions, mixing,
pumping and pressurization, and filtration. Our
research has been involved with both of these
categories, but most recently has focused on nonshaping operations.
POLYMER DEVOLATILIZATION
Our work on the devolatilization of polymeric
materials is concerned with understanding how rates
of interphase mass transfer are influenced by the
viscoelastic nature of polymer melts, the kinematics
of flow–especially extensional flows–and by the
growth and rupture of entrained bubbles. Theoretical
studies have led to a new model for bubble
growth–our "cell model"–and to the design of novel
processes involving extensional flows. Experimental
studies conducted in our laboratories are in support
of our theoretical findings.
SELECTED PUBLICATIONS
“Transient Free-Surface Flows: Fluid Advancing
Through a Bed of Cylinders,” with R.A. Behrens, M.J.
Crochet and A.B. Metzner, AIChE J., 34 (11), 1894
(1988).
“Imidization Reaction Parameters in Inert Molten
Polymers for Micromixing Tracer Studies,” with J.H.
Frey, Chem. Eng. Sci., 43, 1967 (1988).
“Flow in Driven Cavities with a Free Surface,” with
E.L. Canedo, AIChE J., 35 (1), 129 (1989).
“The Determination of Mass Transfer Coefficients for
Bubble-Free Devolatilization of Polymeric Solutions
in Twin Screw Extruders,” with G.P. Collins and G.
Astarita, AIChE J., 31 (8), 1288 (1985).
“Devolatilization of Concentrated Polymeric Solutions
in Extensional Flow,” with J.F. Nangeroni, SPE Reprints,
Antec, Los Angeles, CA (1987).
14
MIXING & CHEMICAL REACTION IN VISCOUS POLYMER
MELTS
The product distributions in polymerization reactions
and in polymer alloys and blends formed by reactive
processing are critically dependent on the
micromixing (i.e., mixing at the molecular level)
which occurs in the geometry in which the process is
being conducted. Our research in this area
addresses the problem of developing an engineering
understanding as to how processing geometry
influences micromixing. These studies are both
theoretical and experimental in nature, and center
around a second-order, competitive-consecutive
reaction pair which we found in our earlier research.
The reaction is conducted in molten polyethylene at
dilute concentrations and traces micromixing in the
particular geometry under study. Processing
geometries which we are presently studying include:
helical-annular geometry, single screw extruders,
and twin screw extruders.
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 15
Faculty
MODELING & KNOWLEDGE INTEGRATION IN CHEMICAL &
BIOLOGICAL SYSTEMS
Our current research combines two decades of
expertise in biotechnology and artificial
intelligence to examine novel applications in
bioinformatics and chemical process fault
diagnosis. In biotechnology, we are converting data
from several levels of hierarchy to knowledge using
system models and knowledge-based approaches.
In chemical process systems, we are analyzing online data using hybrid mathematical-heuristic
approaches to diagnose faults. Common to both
these application areas are the use of dynamic
models, qualitative domain knowledge and
artificial intelligence approaches for data
interpretation and knowledge integration.
BIO PROCESS ENGINEERING
Our past research in biotechnology has resulted in a
better understanding of microscopic and
macroscopic variables that influence the kinetics of
genetically engineered microorganisms. Research by
Mike Betenbaugh, Steve Coppella, Eliana
DeBernardex, Robert Leipold and others examined
the effect of different promoters and host systems for
improved production of proteins. In joint research
with the Pasteur Institute in Paris, Kostas Tokatlidis
examined the effect of gene sequence and protein
structure on the mechanism of inclusion body (protein
aggregate) formation during high-level expression of
cellulolytic proteins in recombinant cells. As part of
collaborative research with Dupont in environmental
biotechnology, Konstantin Konstantinov investigated
the use of bioluminescent recombinant microorganisms as sensors for pollutants. By fusing the lux
genes to stress sensitive promoters, we constructed
genetically engineered cells that give out light when
exposed to pollutants. Isabelle Trezanni (Lyon)
investigated the use of lux genes for on-line
monitoring of intracellular phenomena and modelbased optimization of protein production in the
bioreactor.
KNOWLEDGE BASED EXPERT SYSTEMS/PROCESS FAULT
DIAGNOSIS
In a joint project with Foxboro and DuPont, we were
involved in a pioneering effort for the first industrial
application of an expert system, FALCON (Fault
Analysis Consultant), for fault diagnosis in a
dynamic chemical process (DuPont adipic acid
plant in Victoria, Texas). A key aspect of our work
with intelligent systems is the exploitation of
qualitative domain knowledge from heuristics as
well as quantitative knowledge from mathematical
models. In projects with the Star/Texaco refinery,
we have used a real-time expert system shell G-2
for hydrogen resource management and detection
of odor-causing emissions. We have also used offline archived data collected prior to a refinery
shutdown to "data mine" for indicators that could
have flagged the shutdown prior to its occurrence.
Another project supported by the Army Research
Office involved the application of knowledge-based
systems for intelligent control of composite
manufacturing processes using knowledge
embedded in simulations and combined with
heuristics generated from experiments.
BIOSYSTEMS MODELING & BIOINFORMATICS
We are currently combining our past expertise in
these two areas of biotechnology and knowledgebased systems to examine novel applications in
Bioinformatics. In the area of biotechnology, we are
interested in experimental data involving gene
manipulations and its effects on the whole
organism at a system level. The introduction of a
gene into an organism perturbs it at many levels of
cellular hierarchy. Genomic, Transcriptomic,
Proteomic and Metabolic data provide insight into
the effects of such gene manipulations. We are
modeling these effects and interpreting the large
amounts of data using mathematical models and
qualitative knowledge. The goal is to convert the
massive amounts of data into knowledge at the
metabolic, regulatory, cellular level for the whole
system. We have developed a simulator, eXPatGen,
capable of simulating dynamic gene expression
profiles resulting from complex regulatory
interactions. This simulator can be used to evaluate
multiple ways of analyzing the expression profiles
and determining the best methods of analysis. In a
joint project with Allan Dyen-Shapiro in the Plant
and Science Department, we are developing
mathematical models of signaling pathways in
Arabidopsis disease resistance. The models are
being used to provide hypotheses and guidance for
new experiments. In collaboration with Adam Marsh
in the College of Marine Studies, we are analyzing
gene networks involved in embryonic development
of marine invertebrates and also networks involved
in cold adaptation. Our overall goal is to develop
system level tools for analysis and integration of
information at various levels of hierarchy in
biological systems.
PRASAD S. DHURJATI
Professor of
Chemical Engineering
Ph.D. Purdue
University (1982)
B.S. IIT, Kanpur
(1977)
Biosystems modeling,
bioniformatics,
bioprocess
engineering,
knowledge-based
systems, process fault
diagnosis.
SELECTED PUBLICATIONS
"Properties Conferred on Clostridium Thermocellum
Endoglucanase celC by Grafting the Duplicated
Segment of Endoglucanase celD,” Tokatlidis, K. and
P. Béguin, Protein Engineering, 6, 947-952 (1993).
"Rapid and Sensitive Pollutant Detection by
Induction of Heat Shock Gene-bioluminescence
Gene Fusions,” with Van Dyk, Tina K., W.R. Majarian,
K.B. Konstantinov, R. M. Young and R. LaRossa,
Applied and Environmental Microbiology, 60, 1414-1420
(1994)
"An Intelligent Parallel Control System Structure for
Plants with Multiple Operating Regimes,” with
Kordon, A., Y.O. Fuentes, B.A. Ogunnaike, Journal of
Process Control, 453-460 (1999)
"Thick-sectioned RTM Composite Manufacturing:
Part II. Robust Cure Cycle Optimization and Control,”
with Michaud, D.J. and A.N. Beris, Journal of Composite
Materials, 36, 1201-1231 (2002).
"eXPatGen: Generating Dynamic Expression
Patterns for the Systematic Evaluation of Analytic
Tools,” with Michaud, D.J. and A.G. Marsh,
Bioinformatics (in press).
15
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 16
Faculty
JEREMY S. EDWARDS
Assistant Professor of
Chemical Engineering
Ph.D University of
California, San Diego
(1999)
M.S. University of
California, San Diego
(1997)
Quantitative analysis of
cellular processes,
metabolic engineering
and biotechnology,
bioinformatics and
genomics, genomic
systems engineering,
biological systems
evolution.
B.S. University of
Texas, Arlington
(1995)
SELECTED PUBLICATIONS
“Suitability and Utility of Computational Analysis
Tools: Characterization of Erythrocyte Parameter
Variation,” with Altenbaugh, R.E., and Kauffman,
K.J., Pac Symp Biocomput, 104-115 (2003).
“Evolution Towards Predicted Optimal Growth in
Escherichia coli K-12,” with Ibarra, R.U. and
Palsson, B.O., Nature, 420, 186-189 (2002) .
“Description and Analysis of Metabolic Connectivity
and Dynamics in the Human Red Blood Cell,” with
Kauffman, K.J., Pajerowski, J.D., Jamshidi, N. and
Palsson, B.O., Biophys J, 83, 646-662 (2002).
“Dynamic Flux Balance Analysis of Diauxic Growth in
Escherichia coli,” with Mahadevan, R. and Doyle, F.J.
III., Biophys J, 83, 1331-1340 (2002).
“In silico Predictions of Escherichia coli Metabolic
Capabilities are Consistent with Experimental Data,”
with Ibarra, R.U. and Palsson, B.O., Nat Biotechnol, 19,
125-130 (2001).
16
Our current research activities focus on
computational biology, functional genomics, and
metabolic engineering. The primary goal of these
efforts is to further understand the biological
function of each gene or protein in the context of the
entire cell. Our interest’s range from looking at
microbial systems (i.e. Saccharomyces cerevisiae,
Escherichia coli, or Deinococcus radiodurans) or
more complex multicellular systems (i.e. human or
mouse), and our results will find applications in
many areas; including bioremediation, industrial
microbiology, and medicine.
METABOLIC ENGINEERING
Metabolic Engineering has generated considerable
scientific interest in recent years due to the desire
to redirect metabolic flux for medical and industrial
purposes. The primary goal of metabolic
engineering is to implement desirable metabolic
behavior in living cells through the use of the tools
of recombinant DNA technology. Analogous to
traditional engineering design, the metabolic
COMPUTATIONAL BIOLOGY
Computational Biology has emerged as a very
important aspect of the biological sciences. It is
becoming increasingly obvious that there is not a oneto-one relationship between individual genes and
overall cellular functions; therefore, cataloging and
assigning functions to genes found in a sequenced
genome does not describe the complex relation
between the genetic content and the physiological
function. Since cellular functions rely on the
coordinated activity of multiple gene products, the
interrelatedness and connectivity of these elements
become critical. The coordinated action of multiple
gene products can be viewed as a ‘genetic network’,
which is the collection of gene products that
‘collaborate’ to execute a particular function. To
formulate and study genetic networks, we need to
develop methods that can study the systems behavior
of interacting sets of gene products that underlie the
different cellular functions. These issues rely on
computer science, the physicochemical laws, the
methods of systems science, and a deep
understanding of the biological sciences.
FUNCTIONAL GENOMICS
Functional Genomics has been defined as the
experimental approaches to study genome-wide
gene and protein function. Functional genomics is
differentiated from the tremendous amount of past
biological research in that functional genomics aims
to study the integrated function of the genes and
proteins, rather than studying the function of the
individual genes and proteins. Recent
developments, such as genome sequencing,
proteomics and DNA microarrays, have revolutionized the biological sciences, thus placing us in a
favorable position to decompose the complexities
that link the genetic content to physiological
function (as discussed above). A primary effort in
our research group is developing new tools and
technologies to probe gene and protein function in
a massively parallel manner.
engineer strives to systematically ‘design’ a new
(and improved) living cell, subject to the design
constraints. However, despite the interest in
metabolic engineering, a great disparity exists
between the power of recombinant DNA technology
and the ability to rationally design biochemical
networks. Our research group applies functional
genomics and computational biology tools to guide
the design of biochemical networks for
bioremediation, industrial, and medical
applications.
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 17
Faculty
BRIDGING NANO, MICRO & MACRO SCALES IN COMPLEX
FLUIDS
Our work focuses on developing a comprehensive
understanding of complex fluids through a
hierarchy of scales, by bridging nanoscale
interactions to microstructure, micromechanics,
dynamics, and ultimately, macroscopic properties.
To achieve this, we use novel experimental
approaches that allow us to directly and
simultaneously measure nano- and microscopic
structure and response. These include optical
tweezers, video-rate confocal microscopy, singlepolymer studies and probe particle microrheology.
Below are highlights of our ongoing research in
biomaterials, polymers and colloids, including
systems critical to the development of new
therapeutics, such as engineered tissue
replacements and drug delivery networks for
wound healing, as well as materials found in
numerous manufacturing products and processes.
PARTICULATE GEL MICRORHEOLOGY
Particulate gels occur in a wide range of products
and processes, including coatings, pharmaceutical
formulations, ceramic parts manufacturing,
mineral recovery and lubricant degradation. Gels
form when strong attractions between particles,
induced by van der Waals forces, depletion
interactions, or adsorbing and grafted polymers,
result in aggregation into highly branched, tortuous
structures. We use optical trapping and real-space
imaging to directly measure nano-scale
interactions, microstructure, micromechanics, and
particle rearrangements, to provide a critical
understanding of the mechanisms underlying
macroscopic elasticity and yield behavior in gels.
Microrheology enables us to bridge a wide range of
length- and timescales, induce infinitesimal strains
and stresses, and probe heterogeneity in structure
and mechanics that underlie fracture, compaction,
non-linear response and aging. Our approach is
also being applied to understand microscopic
response in other jammed systems, including
colloidal glasses.
TISSUE ENGINEERING SCAFFOLDS & CELLULAR
MECHANICS
Our work in biopolymers is motivated by the
fundamental roles cellular mechanics, motility and
cell-material interactions play in wound healing,
tissue regeneration, development and cancer.
Underlying these cellular processes is the complex,
highly regulated, system of protein filaments,
cross-linkers, and molecular motors that comprise
the cytoskeleton. Cells, in turn, rely on mechanical
connections to the surrounding extracellular matrix
(ECM), which provides a construct in which they
move, orient and differentiate to form tissues and
organs. While the molecular bases of the
cytoskeleton, ECM and cell-ECM interactions have
been extensively studied, much less is understood
about the mechanical and dynamic response of
cytoskeletal and ECM polymers and networks,
especially for cells in artificial, three-dimensional
tissue scaffolds. We are currently developing
microrheological approaches to understand
material response on the cellular scale. This
enables us to design suitable cellular
microenvironments in scaffolds and networks
using emerging peptidic materials and proteinpolymers.
NANOSCALE STRUCTURE & RESPONSE IN COLLOIDPOLYMER SYSTEMS
Microrheology has been an important tool for
understanding both structure-property
relationships of the reconstituted cytoskeleton and
the fundamental physics of colloid-polymer
systems. Recently, we have been interested in the
structure and response of semiflexible polymer
networks in nanoscale regions surrounding
embedded colloidal probe particles. Using highfrequency tracer probe microrheology, we have
shown that the fluid structure is exquisitely
sensitive to the particle surface chemistry. These
experiments are providing fundamental insight into
entropic depletion effects in colloid-polymer
systems. In addition, our ability to elucidate and
control the the behavior of polymers in highly
localized regions at the solid interface provide a
new means for understanding and tuning the
macroscopic response of filled polymer systems
and composites.
ERIC M. FURST
Assistant Professor of
Chemical Engineering
Ph.D. Stanford
University (2000)
M.S. Stanford
University (1996)
B.S. Carnegie Mellon
University (1995)
Colloid and polymer
physics; microrheology; design and
characterization of
tissue engineering
scaffolds; cellular
mechanics and
motility; complex fluid
structure and rheology.
MOLECULAR MOTORS & ACTIVE GELS
Molecular motors are true nanoengines that
directly convert chemical energy to mechanical
work. These proteins underlie a wide array of
processes in cells and tissues, such as contraction
of smooth and skeletal muscle, cell division,
intracellular trafficking, and endo- and exocytosis.
As mechanical systems are miniaturized to the
nanoscale, a deeper understanding of this
remarkable example of mechanochemistry will be
particularly important, as well. We have recently
used molecular motors to study active dynamics in
cytoskeletal networks. These are important model
systems for elucidating subtle mechanical
properties of semiflexible biopolymers, the nonequilibrium response of the cytoskeleton, and the
mechanics and dynamics of single motor proteins.
SELECTED PUBLICATIONS
“Interactions, Structure and Microscopic Response:
Complex Fluid Rheology using Laser Tweezers,” Soft
Materials, in press.
"Motor-driven Dynamics in Actin-myosin Networks,"
with L. Le Goff and F. Amblard, Physical Review Letters 88,
018101 (2002).
"Micromechanics of Magnetorheological
Suspensions," with A. Gast, Physical Review E 61, 6732
(2000).
"Dynamics and Lateral Interactions of Dipolar
Chains," with A. Gast, Physical Review E 62, 6916
(2000).
"Micromechanics of Dipolar Chains using Optical
Tweezers," with A. Gast, Physical Review Letters 82, 4130
(1999).
17
7258_chemengsingles cc.qxp
8/18/2003
3:34 PM
Page 19
Engineering Around Campus
19
7258_chemengsingles cc.qxp
8/18/2003
3:35 PM
Page 18
Engineering Around Campus
18
7258_chemengsingles cc.qxp
8/18/2003
3:33 PM
Page 20
Faculty
ERIC W. KALER
Elizabeth Inez Kelley
Professor of
Chemical Engineering
Dean, College of
Engineering
Ph.D. University of
Minnesota (1982)
Colloid and surfactant
science, complex fluid
thermodynamics,
materials synthesis,
small-angle scattering.
B.S. California
Institute of
Technology (1978)
Almost all engineering processes involve the
transport of material across an interface. These
interfacial regions are characterized by changes of
composition or density over length scales comparable
to molecular dimensions. Similarly, the composition
and structure of a single phase can vary markedly
over small distances. Examples are liquid crystals,
microemulsions and micelles, some polymeric
solutions, vesicles, emulsions, and protein
dispersions. The physical properties of such complex
fluids make them useful in a multitude of
applications. The best use of these materials,
however, requires knowledge of the arrangement of
the material structure on a molecular scale. With the
goal of developing such an understanding, we are
studying several microemulsions, micelles, and
vesicular dispersions as well as concentrated
colloidal suspensions. The main focus of our work is
experimental, but substantial theoretical and
computational efforts are also underway.
MICROEMULSIONS
SELECTED PUBLICATIONS
“Templating Hollow Polymeric Spheres from Catanionic
Equilibrium Vesicles: Synthesis and Characterization,” with
C. A. McKelvey, J.A. Zasadzinski, B. Coldren and H-T. Jung,
Langmuir 16, 8285 (2000).
“A Class of Microstructured Particles Through Colloidal
Crystallization,” with O.D. Velev and A.M. Lenhoff, Science
287, 2240 (2000).
“Assembly of Gold Nanostructured Films Templated by
Colloidal Crystals and Use in Surface-Enhanced Raman
Spectroscopy,” with P.M. Tessier, O.D. Velev, A.T. Kalambur,
J.F. Rabolt, and A.M. Lenhoff, J. Am. Chem. Soc. 122, 9554
(2000).
“Dielectrophoretic Assembly of Electrically Functional
Microwires from Nanoparticle Suspensions,” with K.D.
Hermanson, S.O. Lumsdon, J.P. Williams and O.D. Velev,
Science 294, 1082 (2001).
“Gaussian Curvature and the Equilibrium Among Bilayer
Cylinders, Spheres, and Discs,” with H-T. Jung, S.Y. Lee, B.
Coldren and J.A. Zasadzinski, Proceedings of the National Academy of
Sciences 99, 15318 (2002).
20
We are examining the structure and transport
properties of microemulsions, with the goal of
developing a better understanding to guide design.
Applications include the use of microemulsions in
many products ranging from cleaners, and
agricultural or cosmetic protein products to
pharmaceuticals. Of special interest are formulations
aimed at reducing the environmental impact of
solvents and surfactants, including the use of
supercritical solvents. The major tools are scattering
experiments, both quasielastic light scattering (QLS)
and small-angle neutron (SANS) and x-ray (SAXS)
scattering. The interactions of colloidal particles and
microemulsion droplets or micelles are also being
examined with applications to problems of colloidal
stabilization.
VESICLES
The uses of vesicles as vehicles for the controlled
delivery of material and for separations processes are
exciting possibilities. We are interested in the
structure and stability of vesicular dispersions, and in
the nature of transport across the
bilayer wall of the vesicle. Studies
of the evolution of vesicle
populations with time, the
transport of ions across vesicle
bilayers, facilitated ionic
transport using ionophores, and
evaluation of vesicle dispersions
for use in a separations scheme
are currently underway.
Theoretical understanding of the
equilibrium between vesicles,
micelles, oligomers, and liquid crystals remains an
important goal. We have also discovered mixtures of
anionic and cationic surfactants in which vesicles
form spontaneously, and this work has opened new
areas of study of the synergism of surfactants.
MATERIALS SYNTHESIS
The use of microstructured fluids in general as
templates for the production of novel materials is
another area of current interest. For example, we are
working to understand the properties of
microemulsions governing their use a substrates for
polymer synthesis, and substantial work is directed
towards measuring and predicting latex sizes and
polydispersities, polymer molecular weights, and
reaction kinetics. We are also interested in the use of
polymerizable surfactants to form new network
structures, and in polymerizing vesicles to make novel
nanoscale polymer particles.
7258_chemengsingles cc.qxp
8/18/2003
3:33 PM
Page 21
Faculty
Combinatorial technologies accelerate the speed of
research, maximize the opportunity for
breakthroughs, and expand the amount of available
information by orders of magnitude compared with
classical discovery methods. Two main obstacles to
the successful application of the combinatorial
approach are the controlled synthesis of small
amounts of materials and the high-throughput
analysis of libraries of these materials. Speed,
through parallel experimentation, is a main
bottleneck in the combinatorial discovery process and
subsequent optimization of novel materials. We have
developed a novel spectral imaging system, which
allows us to simultaneously collect IR spectra of many
members of a combinatorial library with a temporal
resolution around one second, allowing the in situ,
parallel investigation of chemical reactions. We apply
this technique heterogeneous supported catalysts.
COMBINATORIAL CATALYSIS
Catalyst design, which is most crucial for the
development of novel catalytic processes, requires
understanding of the molecular reaction mechanism
and knowledge of the properties that determine the
activity, selectivity, and lifetime of the catalyst.
Studies of the interrelationship between structural
and chemical properties of solid materials and their
catalytic properties are at the origin of catalyst
design. The combination of FTIR imaging with reaction
rate measurements provides us with in situ chemical
information from different adsorbed species on
multiple catalysts under the applied reaction
conditions. By systematically varying the composition
of the various catalysts, we obtain fundamental
structure-composition-function relationships for
catalyst formulations as a function of the active metal
and promoter composition.
CONDUCTING POLYMER NANOFILMS
The realization of the advanced applications of
conjugated polymers greatly depends on the
techniques used to process novel polymers into high
quality ultra-thin films. The major difficulty in
processing conjugated polymers comes from their
insolubility in many organic solvents. In an effort to
overcome this problem, we fabricate polymer
nanofilms by a vacuum deposition/polymerization
process. Vacuum deposition has the advantage of
depositing polymer films in-situ on the substrate;
therefore, insolubility and contamination are no
longer a problem. Time-resolved Fourier TransformInfrared Reflection Absorption Spectroscopy is used
to study monomer adsorption and to follow
polymerization reaction kinetics. We measure the
molecular weight by gel permeation chromatography,
and the thermal stability and adsorption/desorption
kinetics of the monomer are analyzed using
temperature programmed desorption. Our system is
capable of depositing liquid phase monomers by
direct introduction of monomer vapor into the vacuum
chamber. Monomers that are solids at room
temperature can also be studied by heating the
monomer above its melting point and introducing the
resulting vapor. This added capability allows the study
of a much wider range of materials, and also allows
the introduction of photoinitiators, the majority of
which are solids or non-volatile liquids.
CONTROL & MANIPULATION OF NON-LINEAR
HETEROGENEOUSLY CATALYZED REACTIONS
The Langmuir-Hinshelwood mechanism has been
extensively applied to the description of reaction
mechanisms of many industrially significant
reactions. Simplifications in such descriptions are
frequently made, based on ideas of the proper
identification of the rate determining step, and/or the
use of the steady state assumption to simplify
matters. A serious limitation to this approach comes
to light by virtue of the discovery of dynamic patterns
on catalyst surfaces. Simple Langmuir-Hinshelwood
type models are often inapplicable, and can lead to
errors in the extraction of microkinetic information
from experimental data. A systematic and detailed
effort is therefore underway to increase our
understanding of pattern formation and develop
practical strategies to extract microkinetic
information about rate processes from experimental
data more reliably and accurately in the light of our
understanding of pattern formation. Current work in
our lab seeks to explore the perturbation and control
of spatio-temporal pattern formation using
microdosing of reactants onto the surface using a
molecular beam. This experiment affords us the
advantage of studying the effect of local chemical
perturbation on a chemical reaction, thus enabling us
to study, on a mesoscopic scale, the interactions
between incident molecules and adsorbed species.
JOCHEN A. LAUTERBACH
Associate Professor
of Chemical
Engineering
Ph.D. Free University,
Germany (1994)
B.S. University of
Bayreuth, Germany
(1992)
High-throughput
catalysis, fabrication
of conducting polymer
nanofilms, non-linear
dynamics of
heterogeneously
catalyzed reactions,
and time-resolved IR
spectroscopy of
supported catalysts.
SELECTED PUBLICATIONS
"Non-linear Phenomena during CO Oxidation on
Pt(100) – Experiments and Simulations,” with T.
Lele, Chaos, 12(1), 164-172 (2002).
“Combinatorial Approaches to Materials
Development,” with G. Oskarsdottir and C.M.
Snively, Oxford University Press (ACS symposium series
814) (2002).
"Sampling Accessories for the High-Throughput
Analysis of Combinatorial Libraries using Spectral
Imaging,” with C.M. Snively, Spectroscopy, 17(4), 2634 (2002)
"The Effect of Si/Al Ratio and Copper Exchange
Level on Isothermal Kinetic Rate Oscillations for
N2O Decomposition over Cu-ZSM-5: a Transient
FTIR study,” with P.T. Fanson, M.W. Stradt and W.N.
Delgass, Applied Catalysis B-Environmental, 38(4), 331-347
(2002)
"Synthesis and Micropatterning of Semiconducting Polypyrrole Nanofilms by a Two-step
Deposition/polymerication Process,” with J. Bai, C.
Snively, and W.N. Delgass, Advanced Materials (2002).
21
7258_chemengsingles cc.qxp
8/18/2003
3:33 PM
Page 22
Faculty
ABRAHAM M. LENHOFF
Gore Professor of
Chemical Engineering
Ph.D. University of
Wisconsin-Madison
(1984)
M.S. University of
Wisconsin-Madison
(1979)
Transport phenomena,
separation processes,
biophysics and
bioengineering.
B.S. University of
Cape Town, South
Africa (1976)
The main goal of our research is to analyze, control
and exploit molecular interactions involving proteins
and colloidal particles. The motivation is initially to
obtain improved quantitative insights into existing
processes, leading to more effective methods for
designing and using them, but an auxiliary objective is
to develop new products and operations. These
themes bring together a diverse collection of research
activities involving theoretical and experimental work
dealing with both the fundamentals-transport, kinetic
and thermodynamic phenomena-and their interaction
in the process environment.
The path from molecular structure through continuum
properties to process design represents the central
paradigm in modern chemical engineering, but it has
been applied much less extensively to species such as
proteins than to small molecules; such processes as
protein separations still depend very heavily on
empirical methods for design and optimization. Most
of our group's efforts are devoted to understanding
the fundamentals of bioseparations, especially in
chromatography and in separations driven by protein
phase behavior, which are discussed individually
below. We also exploit the propensity of colloidal
particles to self-assemble as the basis for
development of novel materials.
PROTEIN CHROMATOGRAPHY
SELECTED PUBLICATIONS
"A Class of Microstructured Particles via Colloidal
Crystallization,” with Velev, O.D., and E.W. Kaler,
Science, 287, 2240-2243 (2000).
"Determinants of Protein Retention Characteristics
on Cation Exchange Adsorbents,” with DePhillips,
P., J. Chrom. A, 933, 57-72 (2001).
"Rapid Measurement of Protein Osmotic Second
Virial Coefficients by Self-Interaction
Chromatography,” with Tessier, P.M. and S.I.
Sandler, Biophys. J., 82, 1620-1631 (2002).
"Non-Diffusive Mechanisms Enhance Protein
Uptake Rates in Ion Exchange Particles,” with
Dziennik, S.R., E.B. Belcher, G.A. Barker, M.J.
DeBergalis, and S.E. Fernandez, Proc. Natl. Acad. Sci.
USA, 100, 420-425 (2003).
"Predictive Crystallization of Ribonuclease A by
Rapid Screening of Osmotic Second Virial
Coefficients,” with Tessier, P.M., H.R. Johnson, R.
Pazhianur, B.W. Berger, J.L. Prentice, B.J. Bahnson
and S. I. Sandler, Proteins: Struct. Func. Gen., 5, 303-311
(2003).
22
Protein separation processes are crucial to protein
production using modern "genetic engineering"
technology, with chromatography being the workhorse
of most separation and purification processes.
Process models accounting for transport effects
(convection, diffusion) as well as kinetics and
thermodynamics can serve as the basis for scale-up,
but the models require each of the constituent
phenomena to be understood and described
quantitatively; this is the focus of our efforts. We are
seeking in particular to relate key properties of
proteins, e.g., adsorption equilibria, to their molecular
structures. Coupled to this is the role of separations
media, where we are, for instance, examining the
effect of the chemical structure and the pore structure
of chromatographic packings on chromatographic
performance (transport and equilibrium). The
experimental tools that we use provide insights at
levels ranging from macroscopic to molecular; we use
column liquid chromatography, batch uptake
measurements, scanning confocal microscopy,
electron microscopy and colloid science tools such as
scanning probe microscopy (SPM). Similarly, our
theoretical work is performed at different levels: we
seek predictions of adsorption equilibria from
molecular-level computations, and of column
performance from traditional and novel transport and
adsorption models.
PROTEIN SOLUTION THERMODYNAMICS & PHASE
BEHAVIOR
Protein solutions display great complexity in their
phase behavior, with several kinds of equilibrium and
non-equilibrium phases exploited in practice. For
example, protein crystallization is used for
purification, for formulating drugs such as insulin, and
for preparing the protein crystals used in
crystallography; precipitation can be used as an early
step in protein recovery processes; gels are used in
food processing. Many of these applications are
developed empirically, but a more systematic
understanding of protein solution thermodynamics
and phase behavior would facilitate more rational
selection of design and operating procedures.
We would like to understand these aspects more
mechanistically in terms of the molecular structures of
the proteins involved. Again we do so via experimental
and theoretical work at various levels. Our
experimental work includes measurements of protein
interactions, generally in terms of osmotic virial
coefficients, using scattering methods and selfinteraction chromatography, as well as measurements
of phase behavior, including seeking novel
crystallization conditions, guided by the interaction
measurements. These methods are being applied to
both soluble proteins and membrane proteins.
Associated theoretical and computational work is
aimed at explaining trends in the virial coefficient
results and simulating actual phase behavior. For this
purpose we use molecular biophysical methods,
accounting in particular for specific biological
interactions and interactions in which the modulating
role of water is critical.
NOVEL MATERIALS FROM COLLOIDAL SELF-ASSEMBLY
Proteins and colloidal particles share the
characteristic of forming structures with long-range
order. The best known of these are protein crystals,
but colloidal particles can also form crystalline
structures, albeit by a different mechanism. We have
exploited this property for materials synthesis by using
colloidal crystals as templates for making ordered
mesoporous inorganic and metallic structures, which
have potential applications as specialized adsorbents,
catalytic and electronic materials, and substrates for
spectroscopic applications. We have demonstrated
the utility of the materials as a substrate for surfaceenhanced Raman spectroscopy (SERS), which may be
used to detect such moieties as chemical warfare
agents.
7258_chemengsingles cc.qxp
8/18/2003
3:33 PM
Page 23
Faculty
INORGANIC MATERIALS SYNTHESIS & CHARACTERIZATION,
CATALYSIS & KINETICS, & ADSORPTION & SEPARATIONS
Zeolites and other ordered nanoporous materials
are truly fascinating. Not only their wide range of
applications—which include catalytic, adsorption
and ion exchange unit operation, but also their
symmetry, their structural complexity and the
possibility to fine tune their properties to fit a
particular application has made them a subject of
research of ever increasing importance. The
availability of materials with different pore shapes
and sizes—always of the same length scale of small
organic molecules and all of the same size due to
their crystalline nature—are a challenge to scientists
and engineers who want to make a meaningful
contribution to the chemical industries and the
environment. The goal of this research program is to
gain fundamental understanding of the properties
of these materials and the relations of these
properties with the materials structure and chemical
composition. Chemical engineering principles are
then used to modify the properties of the
microporous solids to fulfill the requirements of a
specific application such as a chemical reaction,
the selective adsorption of a particular molecule,
enhanced thermochemical stability, etc.
The catalytic selectivity of crystalline molecular
sieves is mainly controlled by the size and shape of
the pores and cages that form these materials. New
zeolites offer the possibility of carrying out chemical
reactions with an increased level of selectivity and
activity, and one of the main thrusts in this program
is the synthesis of new materials and the
investigation, at a fundamental level, of the
mechanisms of zeolite formation. The
understanding of these mechanisms will open new
opportunities to prepare novel materials with
interesting chemical and physical properties, as
well as new methods to control and modify their
properties systematically. The synthesis of new and
improved adsorption materials depends on a
deeper understanding of the chemical and physical
interactions of organic molecules with the inorganic
zeolite framework. This program also pursues the
investigation of these interactions using a variety of
experimental techniques including solid-state NMR
spectroscopy, IR and Raman spectroscopies, X-ray
diffraction and also advanced theoretical methods
such as molecular dynamics and semi-empirical
quantum-chemical calculations.
We are aiming at the development of a more general
theory that correlates the structure and composition
of the microporous solids to adsorption isotherms,
spectroscopic and optical properties, diffusion
coefficients and the dynamics of small molecules
inside the zeolite pores. Finally, we also pursue the
synthesis of new materials containing organization
in the nanometer length scale. Many of these
RAUL F. LOBO
materials, like polymers in organized mesoporous
inorganic frameworks, or membranes of
Associate Professor of
carbon/silica composites with a well-ordered
Chemical Engineering
mesoscopic structure, are potentially new and very
useful for the separation of gases with high
Ph.D. California Institute
efficiency and at low temperatures. Devising
of Technology (1995)
synthesis strategies that take advantage of the selforganization of polymers, surfactants, biomolecules M.S. California Institute
and inorganic precursors is an area full of
of Technology (1993)
opportunities to discover new materials with
B.S. University of Costa
properties that can be used for the benefit of society
Rica (1989)
at large.
Inorganic materials
synthesis and
characterization,
catalysis and kinetics,
and adsorption and
separations.
SELECTED PUBLICATIONS
"A New Description of the Disorder in Zeolite ZSM48,” with Koningsveld, H., Journal of the American Chemical
Society, 124, 13222-13230 (2002).
"Multiple-quantum H-1 MAS NMR Studies of Defect
Sites in as-made all-silica ZSM-12 Zeolite,” with
Shantz, D. F., auf der Gunne, J.S., Koller, H., Journal of
the American Chemical Society, 122, 6659-6663 (2000).
"Guest-host Interactions in As-made Al-ZSM-12:
Implications for the Synthesis of Zeolite Catalysts,”
with Shantz, D.F., Fild, C., Koller, H., Journal of Physical
Chemistry B, 103, 10858-10865 (1999).
"Characterization of Li Cations in Zeolite LiX by
Solid-state NMR Spectroscopy and Neutron
Diffraction,” with Feuerstein, M., Chem. Mater, 10,
2197-2204 (1998).
"Porous Silica via Colloidal Crystallization,” with
Velev, O.D., Jede, T.A., Lenhoff, A.M., Nature, 389,
447-448 (1997).
23
7258_chemengsingles cc.qxp
8/18/2003
3:33 PM
Page 24
Faculty
BABATUNDE A. OGUNNAIKE
Professor of Chemical
Engineering
Ph.D. University of
Wisconsin—Madison
(1982)
M.S. University of
Wisconsin—Madison
(1982)
Process control,
modeling and
simulation; systems
biology; and applied
statistics.
B.S. University of Lagos
(1976)
PROCESS CONTROL, MODELING & SIMULATION; SYSTEMS
BIOLOGY; APPLIED STATISTICS
Our research efforts are organized around the
general theme of first understanding the dynamic
behavior of complex systems through mathematical
modeling and analysis, and then exploiting this
understanding for novel designs and improved
operation. The particular complex systems of
interest range from polymer reactors, particulate
processes and extruders, to biological systems on
the molecular, cellular, tissue, and organ levels.
When sufficient fundamental knowledge is
available, we develop and employ dynamic
"mechanistic" models; when more data is
available than fundamental knowledge, we apply
probability theory and statistics for efficient data
acquisition and "empirical" model development.
Our research group has three main areas of focus:
•Control and systems theory, where we are
concerned with the development of effective
control techniques, with application to
industrial polymer reactors, distillation
columns, particulate processes, and reactive
extrusion processes; we are also interested in
reverse engineering biological control systems
for process applications.
SELECTED PUBLICATIONS
"The Identification of Nonlinear Models for Process
Control using Tailored "plant-friendly" Input
Sequences," with R.S. Parker, D. Heemstra, F.J.
Doyle III, and R.K. Pearson, Journal of Process Control, 11,
(2), 237-250 (2001).
"A Hybrid Model Predictive Control Strategy for
Nonlinear Plant-wide Control," with G.Y. Zhu and
M.A. Henson, Journal of Process Control, 10, 449-458
(2000).
"Developing an Effective Control Strategy for
Granulation Processes," with A. Adetayo and M.
Pottmann, KONA Powder and Particle, 17, 183-189
(2000).
"Process Control in the evolving Chemical Industry,"
with M.P. Harold, Perspective: A.I.ChE.J., 46, 11, 21232127 (2000).
“Identification and Control Using Volterra Models,”
with F.J. Doyle, and R.K. Pearson, Springer-Verlag,
London, (2002).
24
•Systems biology, where we bring principles of
control and systems theory as well as
probabilistic/statistical techniques to bear on
the analysis of biological processes. We are
developing models, tools and techniques to
study biological systems across various levels
of granularity—from the molecular level where
mechanistic details at the genetic and protein
levels are studied, to the cellular, tissue, organ
and physiological system level. The goals of our
systems biology efforts are to be able to
understand, analyze and predict integrated
biological systems function with sufficient
fidelity for potential practical medical and
pharmaceutical applications.
•Product engineering, Process design and
operations, where we employ both stochastic
and deterministic techniques for engineering
desired characteristics into products, and
subsequently for developing inherently robust
processes to manufacture these products to
meet customer demands consistently in the
face of unavoidable process and raw material
variations.
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 25
Faculty
Our research is generally focused on quantitative
prediction, design, and control of protein degradation
in solution, and of degradation of pharmaceutical and
bio-pharmaceutical molecules in amorphous solids
(glasses); the ultimate goal being quantitative control
of the kinetic stability of labile aqueous and
biological media, and the development of molecularbased engineering models to aid in design of
preservation media for bio- and pharmaceuticalbased materials. Our research incorporates a variety
of tools, including experiment, molecular simulation,
and kinetic and statistical mechanical modeling.
PROTEIN AGGREGATION; PREDICTION OF PROTEIN SHELF
LIFE; PROTEIN PRESERVATION
Proteins degrade in a variety of ways, including
aggregation, oxidation, deamidation, and
hydrolysis. The limited long-term storage stability
of proteins is in fact one of the most difficult
hurdles to commercial development of many
protein therapeutics. Additionally, protein
degradation is implicated in number of devastating
diseases, such as Alzheimer’s and Parkinson’s, but
prediction and control of the underlying processes
remains elusive. Our research in this area is
centered on biophysical chemistry of protein
degradation, as well as the associated
mathematical modeling and shelf life prediction for
proteins. There is particular emphasis on
understanding protein aggregation and other
degradation routes from the perspective of
irreversible interactions between non-native
proteins, solvent-mediated and solute-mediated
forces, interplay between chemical and physical
degradation routes, and the influence of
conformational state on reactivity. Our work utilizes
both experimental techniques (e.g., analytical
chromatography, micro-calorimetry, CD and FL
spectroscopy, and light scattering) and
computational and theoretical tools to elucidate
the role of solvent-mediated interactions and
protein conformation on protein aggregation, both
thermodynamically and kinetically. This knowledge
is in turn used, for example, to develop general
models of protein aggregation kinetics that may be
used to design and/or predict in vitro and in vivo
behavior.
CHRISTOPHER J. ROBERTS
PHARMACEUTICAL & BIOLOGICAL AMORPHOUS SOLIDS
(GLASSES); BIOPRESERVATION
Labile aqueous (biological) systems are inherently
metastable, and will typically degrade upon long
term storage (~ months to yrs.) unless deliberately
preserved. Low temperatures, stabilizing additives,
and/or encapsulation in "inert" solids are
ubiquitous preservation techniques in both
commercial and laboratory practice. Historically,
these approaches have been inspired by
preservation strategies found in Nature, and as
such remain highly empirical. This is particularly
the case for pharmaceutical and biological
systems of commercial interest. The situation is
further complicated by the need in many cases to
rely on (at least partially) amorphous solid or
glassy systems to act as preservation media. Such
glassy systems are intrinsically metastable and
their stability is sensitive to both their processing
history (i.e., how they were prepared) and their
final storage conditions. As a result, traditional
models for crystalline solids or (equilibrium)
liquids are inadequate, and special consideration
of the thermodynamics and molecular dynamics is
required in order to predict and control the
properties of such materials. Work in our group
uses experiment coupled with theoretical and
computational statistical mechanics to develop
more accurate molecular and microscopic models
for the thermodynamics, dynamics, and
degradation kinetics in systems such as glassy bioand small-molelecule pharmaceuticals, food
products, and biological systems under lowmoisture / low-temperature conditions. A common
theme is the development of quantitative
predictive models to allow rational design of biopreservation media, as well to provide insight into
novel experimental methods to preserve such
labile systems.
Assistant Professor of
Chemical Engineering
Ph.D. Princeton
University (1999)
M.S. Princeton
University (1996)
B.S. University of
Delaware (1994)
Preservation of
biological and
pharmaceutical
molecules and
products; protein
aggregation and
chemical degradation;
pharmaceutical
glasses; statistical
mechanics and
modeling of aqueous
media.
SELECTED PUBLICATIONS
"Irreversible Aggregation of Bovine Granulocyte
Colony Stimulating Factor (bG-CSF) and Implications
for Predicting Protein Shelf Life," with Darrington,
R.T. and Whitley, M.B., J. Pharm. Sci., 92, 1095-1111
(2003).
"Kinetics of Irreversible Protein Aggregation:
Analysis of Extended Lumry Eyring Models and
Implications for Predicting Protein Shelf Life", J. Phys.
Chem., 107, 1194-1207 (2003).
"Stabilization of Pharmaceuticals to Oxidative
Degradation," with Waterman, K.C., Adami, R.C.,
Alsante, K.M., Hong, J., Landis, M.S. and Lombardo,
F., Pharm. Dev. Tech., 7, 1-32 (2002).
"Engineering Pharmaceutical Stability with
Amorphous Solids," with Debenedetti, P.G., AIChE J.,
48, 1140-1144 (2002).
"Dissolution Behavior of Porcine Somatotropin with
Simultaneous Gel-formation and lysine Schiff-base
Hydrolysis,” with Ji, Q., Zhang, L. and Darrington,
R.T., J. Controlled Release, 77, 107-116 (2001).
25
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 26
Faculty
ANNE S. ROBINSON
Associate Professor
of Chemical
Engineering
Ph.D. University of
Illinois at UrbanaChampaign (1994)
M.S. The Johns
Hopkins University
(1989)
Molecular and cellular
engineering for
improved protein
production.
B.S. The Johns
Hopkins University
(1988)
SELECTED PUBLICATIONS
“Framework for Modeling Information Flow in Biological
Processes: Application to the Unfolded Protein
Response,” with Kauffman, K., Dhurjati, P., and Doyle
F.J. III, Proc. IFAC Conf. Comput. Appl. Biotech (CAB) (2001).
“Decreased Protein Expression and Oscillating BiP
Levels Result during Heterologous Protein Expression in
S. cerevisiae,” with Kauffman, K., Pridgen, E.M., Doyle,
F.J. III, and Dhurjati, P., Biotech. Prog., 18, 942-940. DOI:
10.1021/bp025518g (2002).
“Rapid Refolding and Polishing of Single-chain
Antibodies from E. coli Inclusion Bodies,” with
Sinacola, J., Protein Exp. Purif., 26, No. 2, 301-308. DOI:
10.1016/S1046-5928(02)00538-7 (2002).
“Expression of an Archael Enzyme in a Eucaryotic Host:
A Secretion Bottleneck at the ER,” with Smith, J.D.,
Biotech. Bioeng., 79, 7, 713-723 (2002).
“Pressure Treatment of Tailspike Aggregates Rapidly
Produces on-pathway Folding Intermediates,” with
Lefebvre, B.G., Biotech. Bioeng, 82, 5, 595-604 (2002).
26
In the post-genomic era, a plethora of data exists
regarding cellular species and their genes, but we
lack data on the properties and processes that lead
to macromolecular and cellular function. The
Robinson laboratory is taking two approaches to
increase our understanding and ability to control
molecular interactions and cellular functions.
MOLECULAR ENGINEERING
Examining proteins in isolation to identify important
self-interactions that influence folding and assembly
to the three-dimensional structure needed for
stability and activity, and controlling those
interactions to optimize this process.
Our research program in molecular engineering has
focused on an understanding of protein folding and
misfolding and developing methods to combat
misfolding and aggregation. Protein aggregation and
misfolding are major obstacles in protein production
in the pharmaceutical and biotechnology industries,
limit the biochemical study of proteins, and are the
proximate cause of the onset of pathogenesis in
several human diseases. The native, correctly folded
state is necessary for a protein’s biological function
and recognition by other molecules; misfolding and
misassembly lead to significant loss of biological
activity. Our approach combines efforts to
understand the molecular interactions that cause
aggregation and to develop strategies to inhibit
aggregation based on this knowledge. Our ultimate
goal is to facilitate production of proteins needed as
therapeutics or for drug discovery efforts, as well as
to enable the inhibition or reversal of disease-causing
aggregation events.
The first step to controlling aggregation is to identify
reactions and critical intermediates during the
competing processes of folding and
misfolding/aggregation. Incorrect association of bsheets has been identified as a key step in
aggregation for P22 tailspike, as well as interleukin1b, transthyreitin, prion protein, and other
amyloidogenic proteins. Our experimental and
modeling approaches have enabled us to identify the
critical intermediates present during aggregation and
folding. We are one of the few groups to identify and
quantify intermediates present in folding and
assembly reactions where both on and off-pathway
reactions can occur simultaneously under
physiological conditions. Using this information, we
aim to develop strategies to decrease aggregation
and increase folding (or refolding) yields, to enable
more efficient protein production in research and
industrial applications.
These approaches have required significant
engineering components, analogous to reaction
engineering of biological systems, where we have
developed both mechanistic and mathematical
models of reactants and rates that are critical to the
analysis and conclusions. This research will result in
more efficient and less expensive routes for protein
refolding and rescue of aggregates, and offers
alternatives for protein families such as membrane
proteins, where traditional refolding approaches have
not been successful.
CELLULAR ENGINEERING
Identifying interactions in the cell that control protein
production and targeting to correct cellular location,
and altering the interactions to maximize production
of functional proteins.
Our research program in cellular engineering has
focused on identifying critical cellular interactions for
two important classes of proteins, integral membrane
proteins and proteins from extremophiles, and for
developing a systems-based approach to
understanding the effects on protein production in
cells. Our goal is to use this knowledge to develop
better cell lines and cellular tools to increase
expression levels. Our laboratory seeks to use a
systematic approach that goes beyond the empirical
observations and optimizations common to more
traditional studies, in order to establish a
fundamental understanding of the key interactions in
these systems.
G protein-coupled receptors (GPCRs) are a large
family of similar seven-helix integral membrane
proteins that mediate cellular responses to diverse
stimuli, including light, hormones, and injury. Many
acute and chronic disease states are linked to GPCR
function, including cardiovascular disease, central
nervous system disorders, metabolic disorders,
inflammation, chronic pain, tumor growth, and
Epstein-Barr infection. Despite their importance, little
is known about expression, folding, and cellular
interactions of these proteins. This limitation is a
major obstacle to elucidation of GPCR structural and
functional properties, and to drug discovery efforts
that target GPCRs. Through molecular labeling of
GPCRs, we have determined that typical cellular
proofreading mechanisms that often limit expression
of soluble proteins do not play an important role in
processing GPCRs. This indicates that either other
mechanisms exist for GPCRs (and presumably other
integral membrane proteins) or that the molecules
themselves play a more critical role, and suggests
new approaches to protein expression such as
engineering new interactions through mutagenesis,
addition/deletion of domains, or through altering
targeting elements.
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 27
Faculty
Our research efforts are oriented toward the
planning and interpretation of experiments, which
produce information needed for the design,
operation and control of commercial scale process
equipment.
SEMICONDUCTOR CHEMICAL REACTION & REACTOR
ANALYSIS
This is a cooperative research effort between the
Department of Chemical Engineering and the
Institute of Energy Conversion (IEC), a laboratory
devoted to thin film photovoltaic research. Chemical
reaction and reactor analysis is applied to the
reactors, which produce the semiconductor layers of
a solar cell. Our goal is to achieve desired electronic
properties of material by controlling the design and
operation of the reactors. We are also concerned
with the design of commercial scale reactors to
produce semiconductor layers since, for
photovoltaic cells, these layers must be deposited
very inexpensively in large areas. Scale-up from
batch laboratory scale (areas of 1 cm2) to
continuous deposition commercial scale (areas over
1m2/min) must be accomplished if cheap
electricity is to be produced from photovoltaic
panels. The first deposition of photovoltaic grade
semiconductor continuously on a moving flexible
substrate was achieved in pilot scale equipment at
IEC and four patents awarded. We have recently
completed a reaction analysis of copper indium
diselenide growth. Species concentrations as a
function of time and temperature have been
experimentally obtained in both a chemical vapor
deposition (CVD) reactor using H2Se to selenize
copper indium layers and a physical vapor
deposition (PVD) reactor using Se to selenize copper
indium layers. Model behavior has been compared
with experimental results to yield reaction rate
constants and energies of activation. The copper
indium diselenide deposition technology developed
by Chemical Engineering and the Institute of Energy
Conversion has been developed to the point where it
forms the basis for a small commercial scale
manufacturing unit built and, operated by Global
Solar in Tuscon, Arizona.
T. W. FRASER RUSSELL
MULTIPHASE FLUID MECHANICS & DESIGN OF MASS
CONTACTORS
Both theoretical and experimental efforts in
fundamental multi-phase fluid mechanics have
most recently addressed the issue of bubble breakup and movement. An understanding of these
phenomena is essential to predict interfacial area in
both tank type and tubular equipment. This research
has led to the development of detailed procedures
for the design of commercial scale gas-sparged
vessels which have been tested in practice.
Allan P. Colburn
Professor of
Chemical
Engineering
Vice Provost for
Research
Ph.D. University of
Delaware (1964)
M.S. University of
Alberta (1958)
B.S. University of
Alberta (1956)
Semiconductor reaction
and reactor
engineering, photovoltaic unit operations,
multiphase fluid
mechanics.
SELECTED PUBLICATIONS
“Applying Microeconomics to Process Design,”
with Ricardo J. Bogaert, I&EC Process Design &
Development, 19, 282 (1980).
“Design of Commercial Scale Gas-Liquid
Contactors,” with Z. Otero Keil, AIChE Journal, 33 (3),
488-496 (1987).
“Experimental Observations of Bubble Breakage in
Turbulent Flow,” with R. P. Hesketh and A. W.
Etchells, I&EC Research, 30 (5), 835-841 (1991).
“Chemical Reaction Analysis of Copper Indium
Selenization,” with S. Verma, N. Orbey, and R. W.
Birkmire, Progress in Photovoltaics, 4, 341-353 (1996).
“Copper Indium Alloy Transformations,” with N.
Orbey, G. A. Jones and R. W. Birkmire, J. of Phase
Equilibria, 21, 6 (2000).
“Reactor and Reaction Model for the Hot-Wire
Chemical Vapor Deposition of Silicon from Silane,”
with A. Pant, and M. Huff, Industrial & Engineering
Chemistry Research, 40, No. 5, 1386-1396 (2001).
27
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 28
Faculty
STANLEY I. SANDLER
H. B. du Pont Chair of
Chemical Engineering
Professor of
Chemistry
Director, Center for
Molecular and
Engineering
Thermodynamics
Thermodynamics,
statistical mechanics,
computational
quantum mechanics,
phase equilibria,
separations processes, biochemical
separations.
Ph.D. University of
Minnesota (1966)
B.S. City College of
New York (1962)
The major expense in the chemical pharmaceutical
industries is the separations and purifications
processes that are largely designed on the basis of
phase equilibrium. Thermophysical properties and
phase equilibria also play important roles in
biochemical processing, environmental engineering
and risk and safety analysis. Our research program
encompasses each of these areas and includes
basic theory, experimental measurements, and
supercomputer simulation.
PHASE BEHAVIOR OF UNUSUAL MIXTURES
One part of our research program is the
measurement of the phase behavior of systems
carefully chosen to test the limits of current activity
coefficient models and equations of state and their
mixing rules. Recent work includes a study of
intramolecular interference or proximity effects in
group contribution methods, and the use of ab initio
quantum chemistry and molecular simulation for
developing new prediction methods. Related work
includes phase behavior measurements of water
pollutants, and modeling of the fate of chemicals
released into the environment.
DEVELOPMENT OF THERMODYNAMIC MODELS FROM BASIC
THEORY
SELECTED PUBLICATIONS
"Ab Initio Intermolecular Potentials for Gas
Hydrates and Their Predictions" with J.B.
Klauda, J. Phys. Chem. B 106, 5722-5732
(2002).
"An Equation of State for Electrolyte Solutions
Covering Wide Ranges of Temperature,
Pressure, and Composition" with J.A. Myers,
and R.H. Wood, IEC Research 41, 2332-2334
(2002).
"Thermodynamics and Bioenergetics" with Y.
Demirel, Biophysical Chem. J. 97, 87-111 (2002).
"Ab initio Pair Potentials and Phase
Equilibrium Predictions of Halogenated
Compounds" by A.K. Sum, S.I. Sandler and
P.K. Naicker, Fluid Phase Equilibria, 199, 5-13
(2002).
"Self-interaction Chromatography: a Novel
Screening Method for Rational Protein
Crystallization" with P.M. Tessier, S.D.
Vandrey, B.W. Berger, R. Pazhianur, A.M.
Lenhoff, Acta Cryst. D Biological Crystallography 58,
1531-1535 (2002).
28
Most of the thermodynamic models presently in use
have been empirically developed by fitting
experimental data. Consequently, neither the
models nor the values of their parameters have a
molecular basis. Also, extrapolation of these models
can lead to serious errors. We have been using a
combination of statistical mechanical theory,
quantum mechanical calculations and molecular
simulation as a basis for computing the
thermodynamic properties and phase behavior, and
to understand local ordering phenomena in models
fluids. From these we have been able to develop
new classes of theoretically based thermophysical
properties models for pure fluids and mixtures.
PHASE BEHAVIOR OF BIOMOLECULAR SYSTEMS
The separation of biomolecules, and especially
proteins and other pharmaceuticals, is an important
problem. Since such molecules have a limited range
stability, separation techniques such as distillation,
extraction with harsh solvents, etc., cannot be used.
We have been studying using experiment, theory,
and simulation the crystallization of proteins.
Central to these studies have been determining the
effects of pH, ionic strength, salts and precipitants
such as polymers on the solubility and
thermodynamics of biomolecules in solution.
EQUILIBRIUM & TRANSPORT IN NANOSTRUCTURED
MATERIALS
The adsorption of gases and their separation
through nanostructured porous membranes, and
the formation of gas clathrate hydrates are
examples of equilibrium and transport through
structures that are of similar size to the molecules
involved. Many of the phenomena that occur are
poorly understood. We have been using
computational quantum mechanics (to calculate
the interactions between the molecules involved)
and both Monte Carlo and molecular dynamics to
compute and model the properties of such systems.
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 29
Faculty
The properties of polymeric materials are often
determined by their structure, especially at the
nanometer and micron length scales. These
microstructural features, in turn, are influenced by
the engineering processes which formed the
polymers, e.g., reaction, thermal history, shaping,
and stretching.
Our research interests in advanced materials focus
primarily on the relationship between processing
and structure in polymeric materials and
composites.
ELECTRORHEOLOGICAL FLUIDS
Electrorheological (ER) fluids are smart materials
whose viscosity and stiffness can be quickly varied
from liquid-like to solid-like with the application of
an electric field. They are receiving extensive
consideration for hydraulic devices such as valves
and clutches, and for vibration damping devices
such as shock absorbers.
ANNETTE D. SHINE
POLYMER PROCESSING WITH SUPERCRITICAL FLUIDS
Supercritical fluids (SCFs) can combine the density
and solvent quality of a liquid with the viscosity and
transport properties of a gas, so they offer attractive
features as potential solvents in various polymer
processes. In many of these processes, both
polymer solution thermodynamics and transport
phenomena (fluid mechanics, mass and heat
transfer) influence the structure and properties. Our
research focuses on SCF processes for producing
fine particles for controlled release drug delivery.
In these processes, biodegradable polymers are
coprecipitated with therapeutic agents such as live
viruses directly into solid particles by lowering the
pressure of a carbon dioxide-swollen polymer.
Through experiments and modeling, we seek to
describe the effect of material, design and
operating parameters on the size, shape and
structure of the drug delivery particles.
Associate Professor of
Chemical Engineering
Ph.D. Massachusetts
Institute of Technology
(1983)
M.S. Case Western
Reserve University
(1979)
B.S. Washington
University (1976)
Rheology and
processing of
polymers; electrorheology; polymers and
supercritical fluids;
drug delivery.
Our research investigates the potential use of liquid
crystalline polymers (LCPs) as ER fluids, especially
in microfluidic applications. LCPs are elongated,
rigid molecules, which adopt a distribution of
molecular orientations at rest, as seen in the
accompanying micrograph. However, when
subjected to a strong orienting field, such as an
extensional flow field or an electric field, the
polymer molecules cooperatively align nearly
parallel to each other. The direction of orientation
can be controlled by the competing effects of flow
field and electric field, with a material response
time on the order of milliseconds.
We are examining the ER effect in LCP solutions
through a research effort that includes molecular
design and synthesis of new polymers, experimental
measurement of flow properties, and theoretical
modeling of electrical and rheological behavior. In
particular we have applied molecular theories to
describe LCP ER behavior, so that we can directly
determine the influence of molecular-level
properties on the rheological behavior of LCP
solutions. This is of tremendous benefit to ER device
designers, who can design both the equipment and
the fluid to meet required specifications.
SELECTED PUBLICATIONS
"Steady-State Electrorheology of Nematic Poly (nHexy1 Isocyanate) Solutions" with K.L. Tse.
Macromolecules 33, 3134 (2000).
"Polymers and Supercritical Fluids" in Physical
Properties of Polymers Handbook, J.E. Mark, ed.,
American Institute of Physics (1996).
"Two-Dimensional Modeling of the Electrorheological Behavior Liquid Crystalline Polymer
Solutions" with K.L. Tse, J. Rheol. 39, 1021 (1995).
"Effect of RESS Dynamics on Polymer Morphology"
with A.K. Lele, Ind. Eng. Chem. Res., 33, 1476 (1994).
"Behavior of Polymer-Supercritical Chlorodifluoromethane Solutions" with C.W. Haschets,
Macromolecules, 26, 5052 (1993).
29
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 30
Faculty
DIONISIOS G. VLACHOS
Professor of
Chemical Engineering
Ph.D. University of
Minnesota (1992)
M.S. University of
Minnesota (1990)
B.S. National
Technical University
of Athens (1987)
Microchemical
systems, fuel
processing, and fuel
cells.
SELECTED PUBLICATIONS
"Recent Developments on Multiscale, Hierarchical
Modeling of Chemical Reactors" with S.
Raimondeau, Chem. Eng. J. 90 (1-2), 3-23 (2002).
"Simulations and Experiments on the Growth and
Microstructure of Zeolite MFI films and Membranes
by Secondary Growth" with G. Bonilla and M.
Tsapatsis, Micropor. Mesopor. Mat. 42 (2-3), 191-203
(2001).
"Spontaneous Formation of Periodically Patterned
Deposits by Chemical Vapor Deposition" with M.
Tsapatsis, S. Kim, H. Ramanan, and G.R. Gavalas, J.
Am. Chem. Soc. 122 (51), 12864-12865 (2000).
"A C1 Mechanism for Methane Oxidation on
Platinum" with P. Aghalayam, Y.K. Park, and N.E.
Fernandes, J. Cat. 213, 23–38 (2003).
"Coarse-grained Stochastic Processes for
Microscopic Lattice Systems" with M.A. Katsoulakis
and A.J. Majda, Proc. Nat. Acad. Sci. 100 (3), 782-787
(2003).
30
MICROCHEMICAL SYSTEMS, FUEL PROCESSING, & FUEL
CELLS
Fuel cells have a tremendous potential for
environmentally benign energy generation in
numerous applications. Possible applications
include portable devices for telecommunications,
computers, and transportation, and stationary
devices for regular or backup power generation
systems. Proton exchange membrane fuel cells fed
with hydrogen and air have the highest potential in
the short term. Widespread commercialization of
the fuel cell technology will depend critically on the
availability of hydrogen and the ability to produce
hydrogen cheaply and in an environmentally benign
way. To meet these challenges, our current efforts
focus on microchemical systems for hydrogen
production for fuel cells and detailed mechanism
development for fuel processing. We construct
predictive mathematical models based on
fundamental fluid mechanics, multicomponent
transport, and detailed chemistry. We combine a
suit of multiscale computational tools ranging from
quantum mechanics such as density functional
theory and semi-empirical techniques, to molecular
dynamics and Monte Carlo simulations for small
scales, to mesoscopic models, to reactor scale
models. Simulations are compared to various
experiments conducted in collaboration or in our
laboratory. Nonlinear dynamics such as multiplicity,
oscillations, and chaos is an integral part of our
research. Modern reduction techniques are
employed to derive simplified, accurate models for
on-line control and design.
NANOPARTICLES AND NANOCOMPOSITE MEMBRANES
Zeolite membranes have significant potential in a
number of applications ranging from separations, to
selective catalysis and membrane reactors, hosting
for growth of opticoelectronic materials, and
selective chemical sensors. A major obstacle in
their commercialization is the lack of understanding
the factors controlling their microstructure. Our
objective is to develop a rational approach toward
optimizing the synthesis of zeolitic nanoparticles
membranes (in collaboration with Professors Lobo
and Tsapatsis). We combine state-of-the-art
simulations, including continuum models,
population balances, and Monte Carlo, with various
experiments, including dynamic light and neutron
scattering, electrophoresis, X-ray diffraction, high
resolution electron and atomic force microscopy,
and NMR to understand colloidal interactions and
growth mechanisms of zeolite nanoparticles and
predict membrane microstructure by front tracking
and level set methods. Finally, we develop
microstructure-transport properties relations by
deriving mesoscopic equations, which integrate
information from quantum and molecular scales to
scales relevant to permeation measurements.
PATTERNED MATERIALS
The fabrication of periodic patterns is desirable for
the development of functional materials and
devices with applications ranging from electrooptics
and photonics, to microreactors and biosensors. We
conduct an experimental and theoretical program to
establish the potential of self-regulated systems for
formation of patterned inorganic materials for such
applications.
Contours of fluid flow
in a microcatalytic
reactor producing
hydrogen for fuel cells.
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 31
Faculty
The interesting and technologically useful
properties of modern, high performance materials
are often a direct result of molecular design of their
underlying micro and/or nano scale structures.
Intelligent materials processing strategies control
this microstructure to achieve a desired molecular
and often, supramolecular structure to meet
specific product performance criteria. Thus, our
research is focused on developing a fundamental
understanding of the connection of molecular,
nano, and micro scale structure on the
thermodynamic and transport properties of
complex fluids and nanostructured materials.
Also of interest is the dynamical behavior of
materials during processing, which can be used to
predict the effects of processing on material
microstructure and hence, final product
performance. This research has broad application
and is supported by numerous international
industrial concerns as well as by the National
Science Foundation. Much of the research is
collaborative with investigators and institutions
from around the world.
COLLOIDAL DISPERSIONS
Research projects in our group have focused on the
fundamental aspects of colloidal dispersions,
especially the link between the colloidal
interactions, hydrodynamics and colloid rheology
and stability. Particulate dispersions are found
throughout the coatings and paint, photographic,
pharmaceutical, and materials industries. These
dispersions may also contain free, adsorbed, or
grafted polymers and surfactants. Our research
combines rheology with novel methods of rheooptics (flow dichroism and birefringence), flow
small angle light scattering, and flow small angle
neutron scattering to interrogate colloidal
dispersions under flow. Electro- and magnetorheological fluids are also under investigation.
Statistical mechanical theories are developed and
tested both at the macroscopic and microscopic
levels to validate predictive structure-property
relations. Fundamental research into the nature of
interparticle interactions and their dependence on
system chemistry provide a foundation for this
understanding. Simulations involving novel
algorithms and massively parallel computers are
employed to connect theory and experiment, as
well as provide quantitative predictions of material
behavior. Self-assembling surfactant solutions,
such as wormlike micelles and multilamellar
vesicles and biopolymers are also being explored
using these experimental and theoretical methods.
Recent applications include the development of
novel, nanocomposite materials for ballistic
protection in conjunction with investigators in the
Army Research Laboratory (Aberdeen) and the
Center for Composite Materials. Collaborative work
with scientists from the DuPont company and the
International Fine Particle Research Institute
focuses on the production of dispersed, stable
nanoparticles by stirred media milling.
LIQUID CRYSTALLINE POLYMERS, POLYMER BLENDS, &
DENDRITIC & HYPERBRANCHED POLYMERS
Liquid crystalline polymers, polymer blends, and
dendritic and hyperbranched polymers are also
under investigation in our laboratory. Our research
seeks to determine the effects of polymer
molecular architecture on polymer rheology, as
well as the effects of flow on polymer blend
morphology. In addition to experimental
investigations using scattering techniques and
rheology, nonequilibrium thermodynamics
modeling has been applied to develop new
theoretical models connecting microstructure and
rheology. Current applications of this research are
in the production of novel, high strength and/or
nanostructured polymer fibers by electrospinning
(joint with faculty in Materials Science) as well as
in medical applications (in conjunction with faculty
at Thomas Jefferson Medical University in
Philadelphia).
MOLECULAR MECHANISMS OF DIFFUSION IN
NANOSTRUCTURED MATERIALS
The molecular mechanisms of diffusion in
nanostructured materials, such as reverse osmosis
membranes and polymer glasses confined in
nanostructured materials are being examined by a
hierarchical approach that combines ab initio
quantum mechanics calculations with molecular
dynamics simulations with mode coupling theory.
Molecular simulations explore the role of matrix
topology and penetrant-matrix coupling on the
selectivity and permeability of reverse osmosis,
polymer glass and nanoporous carbon
membranes. This research includes new
applications of advances in computational
chemistry and parallel computing to explore
molecular motion in nanostructured materials. The
goals of this research are to elucidate the basic
mechanisms underlying the performance of these
membranes and to provide semi-quantitative, ab
initio predictions of membrane performance.
NORMAN J. WAGNER
Professor of
Chemical
Engineering
Ph.D. Princeton
University (1988)
B.S. Carnegie Mellon
University (1984)
Rheology of colloidal
dispersion,
nanoparticles,
surfactant, biopolymer
and polymer solution,
and structured polymers
and polymer blends;
nonequilibrium
statistical mechanics
and thermodynamics of
complex fluids; molecular
mechanics of diffusion in
nanostructured
materials.
SELECTED PUBLICATIONS
“Molecular Dynamics Simulation Study of the
Mechanisms of Water Diffusion in a Hydrated,
Amorphous Polyamide” with M.J. Kotelyanskii and
M.E. Paulaitis, Computational and Theoretical Polymer Science,
9: (3-4) 301-306 (1999).
“Generalized Doi-Ohta Model for Multiphase Flow
Developed via GENERIC” with H.C. Öttinger and B.J.
Edwards, AIChE J. 45(6), 1169-1181 (1999).
“Hydrodynamic and Colloidal Interactions in
Concentrated, Charge-Stabilized Polymer
Dispersions” with F.M. Horn, W. Richtering, J.
Bergenholtz, and N. Willenbacher, J. Colloid. Int. Sci.,
255, 166-178 (2000).
“Flow-Small Angle Neutron Scattering
Measurements of Colloidal Dispersion
Microstructure Through the Shear Thickening
Transition,” with B.J. Maranzano, J. Chem. Phys., 117,
10291-10302 (2002). (Also selected to appear in the
Virtual Journal of Nanoscale Science & Technology, Dec. 2nd, 2002.)
“Fundamentals of Aggregation in Concentrated
Dispersions: Fiber-optic Quasielastic Light
Scattering and Linear Viscoelastic Measurements,”
with Stacey L. Elliott, Robert J. Butera, & Leo H.
Hanus, Faraday Discussion 123, 369–383 (2003).
31
7258_chemengsingles cc.qxp
8/18/2003
3:31 PM
Page 33
Faculty
Materials science and engineering focuses on the
fundamental relationships between microscopic and
macroscopic optical/thermal/electrical/mechanical
properties. We apply this paradigm to our research in
Polymer Interfaces, Dynamics, Composites and
Plastics from Renewable Resources. For example, in
thermoplastic welds, we will try to understand the
strength development and durability of the weld in
terms of the polymer dynamics controlling the
interdiffusion process and the microscopic
deformation mechanisms involving disentanglement
and rupture of chains. By inter-relating microscopic
measurements (e.g., Neutron Reflection, SIMS, XPS,
FTIR) and macroscopic (e.g., Fracture, Fatigue,
Thermal, Optical) measurements on model materials
systems, we obtain fundamental solutions with broad
application.
STRUCTURE & STRENGTH OF POLYMER INTERFACES
We are interested in the time-dependent structure
which develops at polymer and composite interfaces
and interphases, and how these microscopic
structures control the bonding and related properties
of the material. These include (a) Symmetric
amorphous and semi- crystalline thermoplastic
polymer-polymer interfaces, (b) Compatible and
incompatible polymer-polymer interfaces, (c) Crosslinking reacting interfaces, and (d) Polymer-nonpolymer interfaces. Studies on model interfaces have
application to composite processing, intelligent
sensing, recycling and affordable manufacturing.
CRITICAL TESTS OF POLYMER DYNAMICS
We explore dynamics models (Reptation, Rouse,
Mode Coupling, etc.) for highly entangled linear
polymer chains in the melt state using specially
deuterated polystyrene chains. Chains whose centers
are deuterated (HDH) are allowed to interdiffuse with
chains whose ends are symmetrically deuterated
(DHD). When we examine the resulting deuterium
concentration depth profile, we can sensitively
determine which dynamics models are appropriate to
describe the diffusion process as a function of time
and distance. The depth profiling is done by dynamic
Secondary Ion Mass Spectroscopy (SIMS) and
Neutron Reflection at NIST and Argonne National
Labs. The results are important for understanding
polymer rheology and processing.
POLYMER-METAL INTERFACE ADHESION
The goal is to identify in a fundamental manner
factors which control the adhesion of polymer-metal
interfaces and to relate those factors to the chemical
and mechanical durability of industrial materials
systems such as bonded joints, coated products and
composites. In this research we explore the nature of
the bonding between polymers and metal substrates
using model polymers on well characterized metal
substrates. The model polymers consist of linear
polybutadienes (PB), which contain carboxyl groups
(COOH). The latter provide the active bonding sites to
the metal (steel and aluminum) substrate. PB only
weakly adheres to metal, but when COOH groups are
added to the PB chains, the fracture energy increases
considerably. The important question to be addressed
is "What controls the strength increase and can we
optimize it for a given composite configuration?" The
fundamental solution to this problem will enable us to
design improved composite structures, substrate
surfaces, and coupling agents, and to improve the
ability to predict the relative long term performance of
composite systems in different applications and
environments.
AFFORDABLE COMPOSITES FROM RENEWABLE RESOURCES
(ACRES)
The mission of the ACRES research is to promote the
widespread use of composites from renewable
resources (soybeans, starch, natural fibers). The
integrated, cross-disciplinary research program
examines the fundamental issues pertaining to the
manufacture of polymer composite materials from
natural products. The ACRES Project focuses on
affordable manufacturing of polymer composite
materials for potential high-volume applications in the
civil infrastructure, defense, air transport, automotive,
offshore, and aerospace areas.
RICHARD P. WOOL
Professor of
Chemical
Engineering
Ph.D. University of
Utah (1974)
M.S. University of
Utah (1972)
B.S. University
College Cork Ireland
(1970)
Polymer physics,
interfaces,
composites, dynamics,
fracture, biodegration,
materials science.
ENVIRONMENTALLY DEGRADABLE PLASTICS
In this research, we examine how plastics can be
designed to degrade harmlessly and in a controlled
manner in terrestrial and aquatic environments. These
include compost sites, landfills, agricultural
environments, fresh water and ocean environments.
Plastics composites can be synthesized and
formulated with renewable resources such as starch
and cellulose to degrade by synergistic mechanisms
involving biological, chemical and photochemical
processes. The biodegradation rate of model systems
is determined by new ASTM lab test methods,
compared with computer simulations and correlated
with real environmental applications.
SELECTED PUBLICATIONS
“Polymer Interfaces: Structure and Strength,”
Hanser/Gardner Press, New York ISBN 1-56990-133-3,
p.500 (1995).
“Welding of Polymer Interfaces” with B.L. Yuan and
O.J. McGarel, Polymer Engineering and Science, 29 (19),
1340-1367 (1989).
“Interdiffusion of Polymers Across Interfaces” with
G. Agrawal, W.D. Dozier, G.P. Felcher, J. Zhou, S.
Pispas, J.W. Mays, and T.P. Russell, J. Polymer Science,
Part B., Polymer Physics, 34, 2929 (1996).
“Percolation Effects in Degradable PolyethyleneStarch Blends” with J.S. Peanasky and J.M. Long,
Journal of Polymer Science: Part B: Polymer Physics, 29, 565579 (1991).
“Fractal Structure of Polymer Interfaces” with J.M.
Long, Macromolecules, 26, 5227 (1993).
33
7258_chemengsingles cc.qxp
8/18/2003
3:32 PM
Page 32
Faculty
BRIAN G. WILLIS
Assistant Professor of
Chemical Engineering
Ph.D. Massachusetts
Institute of
Technology (1999)
B.S. Northwestern
University, Illinois,
USA (1993)
Experimental and
computational
chemistry investigations of chemical
processes related to
electronic materials,
including silicon and
compound semiconductors.
SELECTED PUBLICATIONS
"Surface Disproportionation of Dimethylalane and
Trimethylalane on Aluminum Surfaces, Part 1.
Experimental Studies", with K.F. Jensen, Surface Science
488, 286, (2001).
"Surface Disproportionation of Dimethylalane and
Trimethylalane on Aluminum Surfaces, Part 2.
Computational Chemistry Studies," with K.F.
Jensen, Surface Science 488, 303, (2001).
"Gas Phase Reaction Pathways of Aluminum
Organometallic Compounds with Dimethylaluminum
Hydride and Alane as Model Systems," with K.F.
Jensen, J. Phys. Chem. A. 104, 7881, (2000).
"An Evaluation of Density Functional Theory and ab
Initio Predictions for Bridge-Bonded Aluminum
Compounds," with K.F. Jensen, J. Phys. Chem. A. 102,
2613, (1998).
"Computational Chemistry Predictions of Reaction
Processes in Organometallic Vapor Phase Epitaxy,"
with H.Simka, I. Lengyel, and K.F. Jensen, Prog. Crystal
Growth and Charact. 35, 117, (1998).
32
Research interests are broadly categorized as
investigations of processing ⇔ properties⇔
performance relationships of electronic materials.
Materials of interest include silicon and compound
semiconductors, and especially the properties of
metallic and dielectric thin films. Current materials
of interest include perovskite films for
heteroepitaxy applications, transition metals for
copper barrier and electrode applications, and
systems engineering of nanometer-scale copper
interconnects. Research tools include
experimental studies of growth processes and
reactive chemistries, and theoretical studies of
reactive chemistries using computational
chemistry methods.
SYSTEMS ENGINEERING OF NANOMETER SCALE COPPER
INTERCONNECTS
Copper interconnect research is focused on
chemical and physical properties of interconnect
structures, and the optimization of “systems”
performance. Copper interconnects are the tiny,
submicron “wires” that connect the millions of
transistors in an integrated circuit. The complexity
of interconnect designs requires “systems” level
understanding of the processing ⇔ properties ⇔
performance relationships of interconnect
materials. Research goals are to optimize systems
performance by identifying chemical and physical
processes critical to the integration of interconnect
materials, and to develop techniques to measure
these properties accurately. As copper wires shrink
below 100nm features, control of the chemicalphysical processes will be essential to realize high
performance and high reliability devices.
COMPOUND SEMICONDUCTOR-SILICON INTEGRATION
Silicon devices dominate microelectronics
technology, but there are important functionalities
that are not effectively integrated with silicon
technology. Light emission from semiconductor
lasers and LEDs (light emitting diodes) as well as
high power microwave frequency devices are
fabricated with compound semiconductors such as
gallium arsenide (GaAs), Indium Phosphide (InP),
and Gallium Nitride (GaN). Ubiquitous, costeffective use of the unique functionalities of
compound semiconductor materials for “system on
a chip” applications requires the integration of
compound semiconductors with silicon technology.
Cost-effective manufacturing considerations
require wafer scale integration through chemical
processing. Perovskite materials such as SrTiO3
have unique properties that offer promise for the
hetero-integration of silicon and compound
semiconductors. Research is focused on the
development of the chemical vapor deposition and
atomic layer deposition of perovskite films for
“buffer layer” applications and compound
semiconductor-silicon integration. Research
activities are concerned with the engineering of gas
phase and surface reaction processes to achieve
monocrystalline, epitaxial layers on silicon. The
oxidation and strain relaxation mechanisms of
perovskite films are also of paramount interest.
The design of new “buffer layer” materials requires
a thorough understanding of these processes.
ADVANCED REACTION ENGINEERING & COMPUTATIONAL
CHEMISTRY
The miniaturization of semiconductor devices
necessitates the continuous introduction of new
materials and chemical processes. The growth of
thin films for electronic properties increasingly
utilizes chemical vapor deposition and atomic layer
deposition techniques to achieve high quality,
conformal thin films. For example, platinum group
metals are presently of great interest as metal
electrodes for high density memory devices with
high dielectric constant insulators. Other refractory
metals such as titanium, tantalum, and tungsten
are used for copper barrier applications. The
organometallic “precursors” used to deposit these
types of films have complex coordination ligands
and complicated gas phase and surface
chemistries. Advanced reaction engineering of
these applications requires thermodynamic and
kinetic data for properties such as heats of
reaction, equilibrium constants, and kinetic rate
constants. Computational chemistry tools have
great potential for computing thermodynamic and
kinetic properties of organometallic reactants. The
computation of thermodynamic and kinetic data
allows the evaluation thin film growth pathways
and the construction of detailed growth models.
Research is focused on developing quantitative
mechanisms for the gas phase and surface
reaction pathways involved in the growth of thin
films for micro/nano-electronics applications.
7258_chemengsingles cc.qxp
8/18/2003
3:31 PM
Page 34
Emeritus Faculty
KENNETH B. BISCHOFF
Unidel Professor Emeritus
Ph.D., Illinois Institute of Technology
(1961)
B.S., Illinois Institute of Technology
(1957)
ARTHUR B. METZNER
H. Fletcher Brown Professor Emeritus
Ph.D., Massachusetts Institute of
Technology
(1951)
B.S., University of Alberta
(1948)
Bioengineering, chemical
reaction engineering
Polymer processing and fiber
spinning, fluid mechanics
JON H. OLSON
Professor Emeritus
Ph.D., Yale University
(1961)
B.S.E., Princeton University
(1955)
JEROLD M. SHULTZ
C. Ernest Birchenall Professor
Emeritus
Ph.D., Carnegie Institute of
Technology
(1964)
M.S., University of California, Berkeley
(1959)
B.S., University of California, Berkeley
(1958)
Kinetics and reactor design,
process control, and aerosols
Materials science, structure
and properties of polymers, Xray diffraction technology
34
7258_chemengsingles cc.qxp
8/18/2003
3:31 PM
Page 35
Affiliated Faculty
Robert Butera, E.I. du Pont de Nemours & Co., Inc.
Arthur Etchells, E.I. du Pont de Nemours & Co., Inc. - Retired
William Farneth, E.I. du Pont de Nemours & Co., Inc.
James Grant, E.I. du Pont de Nemours & Co., Inc.
Robert Grasselli, University of Munich
Richard Grenville, E.I. du Pont de Nemours & Co., Inc.
Allan Jones, E.I. du Pont de Nemours & Co., Inc. - Retired
Richard LaRouche, E.I. du Pont de Nemours & Co., Inc.
Steven Lustig, E.I. du Pont de Nemours & Co., Inc.
James Lyons, The Catalyst Group
William Manogue, E.I. du Pont de Nemours & Co., Inc. - Retired
Kenneth Mulholland, E.I. du Pont de Nemours & Co., Inc.
John Richards, E.I. du Pont de Nemours & Co., Inc.
Mark Schure, Rohm and Haas Company
James Schwaber, Thomas Jefferson University
David Short, E.I. du Pont de Nemours & Co., Inc. - Retired
James Tilton, E.I. du Pont de Nemours & Co., Inc.
Jean-Francois Tomb, E.I. du Pont de Nemours & Co., Inc.
Alan Uebler, Mortenson & Uebler
Kurt Wissbrun, Hoechst-Celanese Research Co. - Retired
Faculty with Secondary Appointments
Douglas Doren, Chemistry & Biochemistry
Kristi Kiick, Materials Science & Engineering
Clifford Robinson, Chemistry & Biochemistry
Klaus Theopold, Chemistry & Biochemistry
Funding
The Chemical Engineering Department gratefully acknowledges financial and other support from the following:
Aerscher Diagnostics
Air Products and Chemical Corporation
Alfred P. Sloan Foundation
American Chemical Society Petroleum Research Fund
Atofina
Basell USA, Inc.
BP Foundation
Camille & Henry Dreyfus Foundation
Clariant Corporation
Compact Membrane Systems
Deere & Company
Dow Chemical Company
DuPont Company
Eastman Chemical
Eastman Kodak Company
ExxonMobil Corporation
ExxonMobil Foundation
Fidelity Investments
Genentech, Inc.
Hercules Incorporated
Hess Foundation, Inc.
ICI Chemical and Polymers
International Fine Particle Research Institute, Inc.
Ion Power, Inc.
Lord Corporation
Lubrizol Corporation
Merck & Company, Inc.
Millipore Corporation
Mobil Foundation, Inc
National Action Council for Minorities in Engineering
National Starch & Chemical Company
Novaflux, Inc.
Philip Morris Company
Procter and Gamble
Rhodia Inc.
Roche Diagnostics Corporation
Rohm and Haas Company
Schlumberger-Dowell Corporation
Shell Oil Company Foundation
The Merck Company Foundation
Unilever Corporation
Union Carbide Corporation
W.R. Grace & Company
Waters Corporation
Westvaco Corporation
Weyerhaeuser Company
35
7258_chemengsingles cc.qxp
8/18/2003
3:31 PM
Page 36
Staff of Chemical Engineering
James Byrnes, Manager, Chemical Engineering Computing Services
David Caldwell, CITA (Computer & Information Technology Association) III
Kim Correll, Records Analyst/Coordinator
Kristine Farmer, Administrative Coordinator
Lillian Grannum, Office Assistant
Patti Hall, Executive Secretary
Deborah Hendel, Administrative Assistant
Lorraine Holton, Assistant to the Editor, AIChE Journal
Carrie McMullen, Administrative Assistant
Trudy Riley, Assistant to the Chair
Kathy Roth, Staff Assistant
Katherine Shearer-Tweedy, Staff Assistant
Susanna Schmid, Staff Assistant
Gary Wellmaker, Sr. Electronics/Instrumentation Specialist
George Whitmyre, Laboratory Manager
Lucille Wilson, Office Assistant
Dawn Yasik, Accountant
Credits
Editing:
Carrie McMullen
Trudy Riley
Design:
Carrie McMullen
Chemical Engineering
Crystal Cox
Graphic Communications Center
Photography:
George Whitmyre
Chemical Engineering
Photographic Services
36
AN EQUAL OPPORTUNITY/AFFIRMATIVE ACTION EMPLOYER—The University of Delaware is committed to assuring equal opportunity to all persons and does not discriminate on the basis
of race, color, gender, religion, ancestry, national origin, sexual orientation, veteran status, age, or disability in its educational programs, activities, admissions, or employment
practices as required by Title IX of the Education Amendments of 1972, Title VI of the Civil Rights Act of 1964, the Rehabilitation Act of 1973, the Americans with Disabilities Act, other
applicable statutes and University policy. Inquiries concerning these statutes and information regarding campus accessibility should be referred to the Affirmative Action Officer, 305
Hullihen Hall, (302) 831-2835 (voice), (302) 831-4563 (TDD).