University
of
New Orleans
Advanced Materials Research Institute
Research
Experiences for Undergraduates Program
Funded
by the National Science Foundation
(NSF
Grants # DMR-0243977 and # DMR-0648962)
Representative
Research Projects - 2008
Electron
Microscopy for Nanomaterials Research,
Dr.
Weilie Zhou, Assistant Professor, Materials Chemistry.
Electron microscopy is a valuable
tool in materials chemistry research. Nanomaterials
structural determination can be performed using scanning electron
microscopy (SEM) and transmission electron microscopy (TEM).
Furthermore, electron lithography patterning can be used for
fabrication of nanomaterials, nanodevices, and nanosensors. While
electron microscopy is a complicated field, we have previously trained
high school students and teachers on its use. These students and
teachers have successfully utilized electron microscopy in completing
independent summer research projects. Undergraduate
students will be trained to operate the scanning electron microscope
(SEM) and transmission electron microscope (TEM). They will also receive
basic training on the fundamental theory of electrons and their use in
materials chemistry. Students
will prepare samples using cutting, grinding, and polishing machines.
The precise dimpling machine and ion milling machine will also be
employed to prepare plane and cross-sectional samples for
semiconductors, magnetic thin films, and superconductors. Scanning
electron and transmission electron microscopes will be used for
structural characterization. The student will utilize our dark room or
digital imaging system to perform structure analysis and our
state-of-the-art electron lithography patterning system to perform
pattern and array writing on various wafers.
The undergraduate participants will gain valuable skills in
electron microscopy. In
addition, they will learn basic laboratory techniques for manipulating
chemicals and equipment for new materials fabrication and
characterization.
Synthesis of Chiral Intermediates for Pharmaceutical Compounds and Self
Assembling Systems, Dr.
Guijun Wang, Assistant Professor of Chemistry.
We are interested in designing and synthesizing chiral compounds
that have potential biological activity. Many natural products or drugs
contain at least one chiral center. The preparation of chiral
intermediates is important in the synthesis of novel pharmaceutical
compounds and self assembling advanced materials. The students will
learn basic organic synthesis technique including setting up reactions
and purification of products. They will also learn separation techniques
by chromatography and basic characterization methods for organic
molecules by NMR, etc.
Biocompatibility of Nanoparticles,
Dr.
Zeev Rosenzweig, Professor of Chemistry. This
project will include studies on the effects of nanoparticles on cells.
The hypothesis to be tested is that unmodified polymeric, metal and
semiconductor nanoparticles have cytotoxic effects on cells that may
lead to changes in growth rate, cell death (apoptosis), or to mutations
leading to carcinogenesis.
On the other hand, surface modification of the nanoparticles, for
example by coating them with a phospholipid bilayer membrane, would
decrease their cytotoxicity and enable their use as intracellular
probes.
Undergraduate students will synthesize and characterize
polymeric, metal and semiconductor nanoparticles with and without
surface modification in the laboratory of Dr.
Zeev Rosenzweig
at AMRI. The students will
test the effect of nanoparticles on murine macrophages that internalize
nanoparticles spontaneously in collaboration with Dr. Nitsa Rosenzweig
of
Xavier
University
. They will determine the
effect of nanoparticles with and without surface modification on cell
growth profiles. They will
also study the molecular effect of these nanoparticles on the cells
using selective assays for apoptosis and carcinogenesis.
The students will gain valuable experience in the synthesis of
nanomaterials, their characterization, and their application in
biological systems. Due to interdisciplinary nature of this
collaborative project, the students will gain experience in a variety of
characterization techniques including electron microscopy, fluorescence
microscopy, cell culture immunological assays, and enzyme assays.
From Chemistry Lab to Magnetic Hard Drive,
Dr.
Leonard Spinu, Associate Professor of Physics and Materials Science.
In
this summer project we will involve undergraduate students in our
research program pursued in AMRI’s
Measurements laboratory. Essentially this activity with undergraduate
students will be integrated in our research of developing novel magnetic
materials with superior properties to be used for high density magnetic
recording media. The main
objective of this summer project is to develop the skills of
undergraduate students so that they learn the scientific approach
necessary for a productive research activity. Specifically, the students
will learn all the steps involved in magnetic and structural material
characterization:
-
In
the chemistry lab, materials will be synthesized, and the samples
will be prepared for magnetic study.
-
The
samples will be magnetically characterized through various magnetic
measurements using equipment in AMRI’s
measurements lab: SQUID magnetometer, VSM magnetometer, or Physical
Property Measurement System (PPMS).
-
Structural
analysis will be performed using AMRI’S main facilities: X-ray
diffraction, Transmission Electron Microcopy, Magnetic Force
Microscopy.
-
Correlation
between the magnetic characterization data and structural properties
will be performed.
-
Based
on the results obtained new material designs will be pursued.
An
important part of the project will be devoted to training the student in
operation of the above
mentioned research tools. The laboratory and characterization activities
will be enhanced with other formative
activities such as bibliography search, preparation of scientific
papers, and preparation of scientific
presentations. By the end
of this project the undergraduate will gain fundamental practical and
theoretical knowledge in magnetism, magnetic characterization
techniques, and cryogenic techniques.
Synthesis
of Novel Nanocomposites for Photocatalysis,
Dr. Matthew Tarr, Professor of Chemistry.
Titanium dioxide (titania) is a useful photocatalyst that can be
used for pollutant destruction or for killing disease cells or
pathogens. We produce and
characterize titanium dioxide nancomposites with various metals, such as
gold, silver, platinum, palladium, or copper attached to the titania.
Subsequently, we test their ability to serve as photocatalysts
for pollutant degradation. In
separate studies, we functionalize the nanoparticles with antibodies and
test their ability to selectively kill disease cells such as cancer
cells. In addition to pure
titania, we utilize modified titania with improved near UV and visible
absorbance in an effort to increase the efficiency of solar-driven
photocatalysis. This project
involves preparation of nanocomposites; characterization of
nanomaterials using transmission electron microscopy (TEM), X-ray powder
diffraction, and absorbance spectroscopy; and determination of
photocatalysis rates using spectroscopic and chromatographic techniques.
Single
Crystal and Powder X-ray Diffraction Studies of New Materials, Dr.
Edwin Stevens, Distinguished Professor of Chemistry (some projects in
collaboration with Dr. Cheryl Klein at
Xavier
University).
This
research project will involve experimental determination of the
molecular structure of crystalline samples using X-ray diffraction.
Samples for study will be selected from the synthetic research
projects of AMRI and Chemistry Faculty.
The samples may include compounds being designed for anti-cancer
activity, antagonists for cocaine, energetic materials, novel chemical
catalysts, and other compounds of current synthetic interest in AMRI and
the Chemistry Department. Students will recrystallize
samples if necessary, select crystals suitable for study by microscopic
examination of samples provided, mount the crystals on a
state-of-the-art automated X-ray diffractometer,
monitor data collection, and process, solve and refine the data
collected on PC's located in the X-ray
laboratory. Students will
prepare graphical displays of the structure and prepare the final
results for publication in appropriate scientific journals. Students
participating in this project will gain hands-on knowledge of the
three-dimensional nature of chemical compounds.
They will also be exposed to concepts in the structure-based
design of new compounds with desirable chemical, pharmaceutical, or
materials properties. Manipulation
of samples and crystallization are additional skills that will be
learned by the participants.
Electronic
Transport Properties of Nanoparticle Assemblies, Dr. Kevin L.
Stokes, Associate Professor of Physics. Our research
is concerned with electronic transport properties of assemblies of
nanometer-sized particles. Specifically, we are measuring electrical
conductivity, thermal conductivity, Seebeck
coefficient and Hall effect on films made of
isolated and electrically connected semiconductor nanoparticles (PbTe,
Bi2S3 and Bi1-xSbx
alloys). The undergraduate students will be involved in all aspects of
this research project including the chemical synthesis of the
nanoparticle colloids, deposition of the thin films, sintering,
measuring the electronic transport properties, preparing samples for
electron microscopy, and analysis of the data. The procedures have been
established, and now can be applied to systematic studies, for example,
like investigating the effect of different deposition or sintering
conditions on the transport properties of the nanoparticle films. The
students will learn how to perform basic electrical transport
measurements on solids and, equally important, how to document
scientific research. They
will also learn some solid-state physics - the basics of electronic and
thermal transport in semiconductors and metals, how these macroscopic
physical phenomena are related to the intrinsic and extrinsic properties
of a real solid material, and what effect, if any, does reduced
dimensionality have on these properties.
Synthesis of Nanophase Particles and Nanocomposites,
Dr. Charles O’Connor, Distinguished Professor of Chemistry and
Director of AMRI.
The focus of this project is devising
synthetic strategies that lead to nanostructured
materials with novel and enhanced properties.
Recent research of our team has focused on the synthesis via a
water-in-oil microemulsion method.
These microemulsions consist of an
aqueous phase that contains the reactants, an oil phase (a non-polar
solvent like octane), a surfactant molecule [e.g. cetyltrimethylammonium
bromide (CTAB) or bis(2-ethylhexyl) sodium sulfosuccinate
(AOT)] and possibly a cosurfactant (e.g. butanol).
Reverse micelles allow the synthesis of a variety of monodispersed,
well-shaped materials without further need for a size-selective
procedure. Undergraduate
students will gain experience in the synthesis, manipulation, and
characterization of nanophase particles
with the eventual use of the particles and assemblies for sensor
applications.
Micromagnetics
of Nanoshaped Magnetic Elements,
Dr.
Scott L. Whittenburg, Professor of Chemistry. Micromagnetics
is the application of numerical methods to solution of the Landau-Lifshitz-Gilbert
equation for the evaluation of magnetic properties of materials.
In recent years the desire for very high density magnetic storage
has led to a decrease in the size of magnetic elements into the regime
where high-level micromagnetic simulations
are now feasible. Such
simulations have demonstrated that the shape of the magnetic element is
crucial in determining the hysteretic, and therefore storage, properties
of the sample. These
simulations are ideal research projects for undergraduates as the
project requires little or no programming experience as we use the
public-domain code from NIST, OOMMF, or our in-house Java-based code, JaMM.
Also, publishable-quality results can be obtained in a reasonably short
period of time. Students
will gain experience in simulation methods used in industry, a
fundamental knowledge of magnetization in materials, and, if desired,
applied programming training. In
addition, students will become familiar with magnetic properties and how
the chemical and physical attributes of new materials influence the
magnetic properties.
Synthesis
and Characterization of Thin Magnetic Films,
Dr.
Leszek Malkinski, Associate Professor of Physics and
Materials Science. The
participant involved in the summer research project will have a chance
to get practical experience in deposition of thin magnetic films.
There are two sophisticated deposition systems available in AMRI's
Thin Film Laboratory: magnetron sputtering system and combined
sputtering/molecular beam epitaxy (a
special kind of evaporator) system. The participant
will be trained to operate at least one of the systems
under supervision of an experienced faculty member. The participant will
also assist in the characterization of structural and magnetic
properties of deposited thin film structures and evaluation of
experimental data. The research is focused on two types of structures:
arrays of very small (nanosized) magnetic
dots and spin tunneling junctions which have a potential to be used in
magnetic recording and computer devices. The time spent in the lab will
give the participant valuable experience in research on advanced
technologies.
Structure and Composition of Nano-Scale
Materials (How to look at small stuff),
Dr.
Heike Gabrisch, Assistant Professor of Chemistry
and Materials Science. Research
at AMRI focuses on materials with special properties, e.g. materials for
batteries, for spintronics or for
bio-medical applications. Often these properties are determined by
features (structure, compositional changes) in the nanometer range. In
order to characterize these materials, techniques like transmission
electron microscopy, scanning electron microscopy, atomic force
microscopy X-ray diffraction etc are used. To help students and faculty
to use these techniques effectively in their research and to improve the
quality of data, we develop interactive web-based teaching/learning
tools. The package is platform-independent and can be used on
workstations at UNO, but also, via the internet or from a CD, at home.
Content in the form of text, images, animations and simulations, image
libraries, videos etc. can be embedded in the browser interface in form
of JAVA applets, video-sequences, remote-control microscopy links etc.
The package is designed to make use of the unique possibilities of the
computer to visualize complex concepts that involve movement, a time
component or 3-dimensional views. The student will have the opportunity
to learn the basic principles of materials characterization techniques
practically in the lab and be involved in designing and preparing
teaching materials for this project. The project will be the basis for a
module geared towards high school students to be used in science classes
or as an introduction for lab visits.
Low
Temperature Preparation of New Oxides,
Dr. John B. Wiley, Professor of Chemistry.
Our group has successfully developed a series of low temperature
methods (# 500 EC) for the synthesis of new non-molecular compounds.
The participant that works in our lab will continue research in
this area with a focus on the synthesis and characterization of new
oxides. He/she will be
exposed to a variety of traditional and nontraditional solid-state
synthetic methods as well as the techniques commonly used in the
characterization of such materials including X-ray powder diffraction,
thermal analysis, magnetic and electronic characterization and elemental
analysis. We have extensive
experience in this chemistry so that the project assigned to the
participant will be one with a high success level in a short period of
time.
The Role of Enzymes in
Phycobiliprotein Biosynthesis, Dr. Wendy Schluchter,
Associate
Professor
of
Biological
Sciences.
The brilliantly colored phycobiliproteins, major components of
the light-harvesting complexes used for photosynthesis in cyanobacteria,
are composed of two different polypeptides.
Each protein subunit carries at least one (and as many as 3)
covalently attached bilin chromophores. The long-term goal of this
research project is to understand how cyanobacteria synthesize and
degrade phycobiliproteins and their bilin chromophores. A major goal is
to characterize enzymes that are involved in attaching the bilins to
phycobiliproteins. The role of enzymes in phycobiliprotein biosynthesis
will be characterized through the generation of knock-out mutants and by
enzyme assays. Students will
be involved in cloning genes and in purifying enzymes we believe are
important in this process, learning molecular biology and biochemical
techniques.
Environmental Biochemistry of Fish, Dr. Bernard Rees, Associate
Professor of Biological Sciences.
The Rees lab uses inter-disciplinary approaches to understand how
fish respond to natural and made-made stressors in the aquatic habitat.
An example of a natural stressor is low oxygen, which brings
about a suite of molecular biological responses in fish and other
aquatic organisms. To study
changes in protein expression during low oxygen exposure, students in
the Rees lab separate proteins by electrophoresis and, in collaboration
with faculty in Chemistry, use mass spectrometry to identify proteins
whose abundance is affected by oxygen availability. With
respect to man-made stressors, one project is designed to evaluate the
effects of pollution on fish development, physiology, and molecular
biology. Techniques of
analytical chemistry are used to identify and quantify specific
pollutants in water and in biological tissues, and a variety of
biological end points are measured in fish exposed to these pollutants.
