Department of Mechanical and Aerospace
Engineering
Abstracts
2004 - 2005
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479 EBU-II
Michael P. Tolocka
Department of Chemistry and Biochemistry
The
Organic Particles in Ambient Air:
How Are They Formed And What Do They Tell Us About The Air We Breathe?
Many studies have linked airborne particles to adverse health and environmental effects. The chemical composition of an individual particle will vary according to its source and subsequent transformations in the atmosphere. Chemical composition measurements provide a means to identify particle sources, to assess their impact on human health and the environment, and to implement effective control strategies to reduce air pollution.
In our recent work, a battery of mass spectrometry techniques was used to characterize organic components in aerosols. The advantages and limitations of these methods for chemical composition measurements, examples of information gained from each, and the significance of these measurements in the context of human health and/or particle formation and growth processes will be discussed.
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479 EBU-II
Effects of Photochemistry on
Source Apportionment of Organic Aerosols
Using Molecular Markers
Organic
material contributes a significant fraction of fine particle mass across all
regions of the
Individual
organic compounds such as levoglucosan and hopanes are often used as tracers for sources of primary
organic aerosol. An important question is the stability of these reduced
organic compounds, particularly in the eastern US and other areas where long-range
transport is an important contributor to ambient aerosol concentrations. This
seminar examines evidence of photochemical aging of molecular
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479 EBU II
Daniel P. Raymer, Ph.D.
President
Conceptual Research Corporation
“Micro-X
Rocket Powered Technology Demonstrator for Responsive and Reusable Access to
Space”
A six-company team headed by Conceptual Research
Corporation is developing a design concept for a rocket-powered technology
demonstrator under funding from USAFWPAFB, with administrative and technical
assistance from the
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479 EBU-II
Professor Shaochen Chen
Mechanical Engineering
The
Laser-Nanostructure Interactions:
Nano-Optics, Surface Engineering, and Heat Transfer
Lasers are becoming important tools for scientific research and industrial applications. The goal of our laboratory is to investigate laser-material interactions at extremely short time and length scales and develop advanced micro/nano-systems for applications in biomedical engineering, the life sciences, and energy systems. In this talk, I will discuss our laboratory's research progress in laser interactions with nanostructures and associated issues of nanoscale optical enhancement, thermal/fluid transport, and nano-patterning. Topics to cover include (1) optical enhancement using near-field effects, surface plasmon effects, and multiphoton effects; (2) thermal/fluid transport involving near-field heat transfer and nanoscale surface tension driven flow for surface patterning; and (3) nanoparticle-enhanced laser materials processing for nanoimprinting and direct-write processes. I will also discuss several engineering applications including the development of micro/nanoscale 3-D scaffolds for tissue engineering, advanced biosystems with nanoscale control of growth factors and topography for nerve regeneration, and nano-textured surfaces for improved mechanical properties.
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479 EBU-II
Dr. Yuntian T. Zhu
Materials Science and Technology Division
Nanomaterials for
Aerospace Applications
Materials for aerospace applications such as airplanes and space shuttles are required to have high strength and light weight. After decades of extensive research and development, conventional materials have reached their limits in terms of their strengths. Nanomaterials are significantly stronger than conventional, coarse-grained materials and offer potentials for improving current aerospace structures and for enabling new space adventures. In this talk I'll present nanostructured metals and long carbon nanotubes, both of which are promising new aerospace materials.
Nanostructured metals can have strengths that are several times higher than their coarse-grained counterparts. However, they often have low ductility, with only a few exceptions. Both high strength and good ductility are desired for structural applications. To tailor nanostructured metals for both high strength and good ductility, we need to first understand their deformation physics. I will present our recent work on the deformation physics of nanostructured metals as well as preliminary evidences that nano-metals can be tailored to have both high strength and good ductility. Carbon nanotubes are 100 times stronger than steel but only one-sixth as heavy. Long carbon nanotubes are the key to utilize their high strength. I'll present the synthesis of 40-mm-long carbon nanotubes and intramolecular nanotube junctions as well as their potential applications in aerospace and other advanced applications.
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479 EBU-II
Cengiz
S. Ozkan
Assistant Professor of Mechanical Engineering
Co-Faculty of Electrical and
Bio-Inorganic Interfaces for Engineering Applications
The integration of soft biological and organic molecular assemblies with hard inorganic nanomaterials or nanoarchitectures is of great interest because it provides opportunities to combine disparate chemical and physical properties in a single system. The goal is to create entirely new classes of materials or devices with tailored functionalities unattainable with individual components. In this talk, I will describe the role of bio-inorganic interfaces in areas of cellular signal detection, scaffolding and nanoassembly of structures. For cellular signal detection, live cells are interfaced with conventional microarray devices for achieving cell based sensing systems. The excitable membrane of neurons provides for a multifunctional transducer where modulation of the firing rate is used for the detection of chemical agents. Next, applications of nanostructured surfaces as novel scaffolds for promoting cellular growth will be discussed. Specifically, the use of carbon nanotube arrays for the guiding of neurites and forming synaptic junctions will be presented. Finally, the use of oligonucleotides as linkers for the self-assembly of carbon nanotubes and quantum dots for fabricating functional nanostructures will be discussed. The robustness and electronic properties of nanoscale inorganic materials can be combined with the molecular selectivity of DNA and PNA for applications in nanoelectronics.
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Thursday, March 24, 2005
10:00 a.m.
479 EBU-II
The
"Geometric Mechanics and Biomorphic
Locomotion in Fluids"
Biomorphic designs for aquatic and aerial vehicles offer advantages in energy efficiency, agility, and stealth. Animals that swim or fly, however, often derive superior performance through subtle, controlled interactions with their environments. The realization of engineering systems which enjoy similar performance requires the development of appropriate modeling, analysis, and control methods as well as novel sensors and actuators. Differential geometric concepts unify the realization and analysis of reduced-order models for complex mechanical systems and the treatment of nonlinear control problems, but the fluid-structure interactions central to macroscopic swimming and flying fall outside the traditional scope of geometric mechanics. This talk will describe the treatment of phenomena like lift generation through vortex shedding in the context of Lagrangian and Hamiltonian systems, the formulation of control problems for energy-efficient underwater locomotion, and the development of a robotic platform for autonomous mobile aquatic sensor networks.
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479 EBU II
Dr. Hana El-Samad
Department of Mechanical and Environmental
“Biological Design Principles For Robustness,
Performance and Selective Interactions with Noise: A Systems Engineering Perspective”
We advocate the use of a systems approach in the modeling and analysis of gene regulatory networks and summarize our work on the modeling of the heat shock response, a cellular system of utmost physiological importance. The heat shock response refers to an intricate set of feedback and feedforward mechanisms that organisms employ to combat the harmful effects of unmediated temperature increases. We illustrate how mathematical models of these mechanisms provide valuable insight, explaining dynamic phenomena exhibited by wild type and mutant heat shock responses, corroborating experimental data and guiding novel biological experiments. Since gene regulatory networks, including the heat shock system, are permanently affected by various sources of noise, we briefly discuss some principles of noise attenuation and exploitation that seem to be at work in these circuits. We argue that a meaningful study of stochastic behavior in these systems should reach beyond arguments based on the number of molecules. It should instead emphasize their dynamic properties and structural features. We conclude with a perspective on future research directions, including theoretical aspects of multi-scale stochastic methods and moment closure techniques for stochastic modeling and analysis of genetic networks.
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Information: (858) 534-0113