Conferences, Lectures, & Seminars
Events for February
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The Multiplying Potential of People, Technology, and Resources, Dr. J. Khalaifa, Saudi Aramco
Thu, Feb 02, 2006 @ 12:00 PM - 01:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
The Society of Petroleum Engineers 2007 President Elect Dr. J. Al-Khalaifa will be visiting the USC Campus and will be the speaker at the USC SPE Student Chapter meeting.
Location: Hedco Pertroleum and Chemical Engineering Building (HED) - co 116 Petroleum and Chemical Engineering
Audiences: Everyone Is Invited
Contact: iraj ershaghi
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Materials Science Seminar- Protein Dynamics At Atomic Scale
Fri, Feb 03, 2006 @ 02:45 PM - 03:30 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Joint Seminar between the Mork Family Department of Chemical Engineering and Materials
Science and the
Department of Physics and AstronomyDongping ZhongDepartments of Physics, Chemistry and Biochemistry,
Programs of Biophysics, Chemical Physics and Biochemistry,
The Ohio State University, 191 West Woodruff Avenue, Columbus, OH 43210, USAProtein dynamics is a complex process and the current challenge is to break down its complexity into elementary processes which act on different time scales and length scales. We integrate femtosecond spectroscopy, molecular biology techniques, and computational simulations to study functional evolution in real time and thus elucidate the complex dynamics with unprecedented detail. Here, two important biological systems, protein surface hydration and light-driven DNA repair, will be reported. With femtosecond temporal and single-residue spatial resolution, we mapped out the global water motion in the hydration layer using intrinsic tryptophan residue to scan the protein surface with site-directed mutagenesis. The results reveal the ultrafast nature of surface hydration dynamics and provide a molecular basis for protein conformational flexibility, an essential determinant of protein function. For DNA repair, we followed the entire functional evolution through femtosecond synchronization. We resolved a series of ultrafast processes including active-site solvation, energy harvesting and transfer, and electron hopping and tunneling. These results elucidate the crucial role of ultrafast dynamics in control of biological function efficiency and lay bare the molecular mechanism of DNA repair at atomic scale.
Location: Vivian Hall of Engineering (VHE) - 217
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Lyman L. Handy Colloquium Series
Thu, Feb 09, 2006 @ 12:45 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Lyman L. Handy ColloquiumMeasurement of Molecular and Thermal Diffusion Coefficients
in Multicomponent MixturesDr. Abbas Firoozabadi
Yale University and RERIAbstract Molecular, pressure, and thermal diffusion processes are important in a variety of disciplines including a vast number of problems related to the exploitation and production of hydrocarbons and improved oil recovery in fractured petroleum reservoirs. The combined effect of these diffusions can result in the unusual floatation of a stable heavy fluid on the top of a light fluid in certain mixtures of interest in hydrocarbon reservoirs.
The study of diffusion processes in mixtures with three and higher species has been a challenge. Multicomponent diffusion is much more complicated than diffusion in binaries; there are some inherent differences between binary and ternary mixtures. Few measurements of molecular diffusion coefficients for multicomponent mixtures have been reported in the literature, even for ternaries. Current techniques are relatively slow and it takes several days to conduct a single measurement. Since the early twentieth century, a variety of methods have been developed to measure thermal diffusion coefficients. The two main methods are:1) the thermogravitational column technique and 2) the optical methods. There is only one report of measurements in a ternary mixture by a thermogravitational method. All the optical techniques have only been used to determine molecular and thermal diffusion coefficients for binary mixtures.
In this talk, I will present a theory and derive working equations for determining thermal and molecular diffusion coefficients in multicomponent mixtures. An analytical model will be presented for the unsteady state behavior of multicomponent mixtures in a thermogravitational column and in an optical diffusion cell using laser beams. In the past, a major drawback with the beam deflection technique has been its limitation to binary mixtures. This is because the measured quantity is the components' net effect on the deflection of the beam rather than the concentration of each individual component. The beam deflection technique can only provide 2(n-1) coefficients, while n(n-1) diffusion coefficients define an n-component mixture. We have solved this problem by using beams of different wavelengths and have developed the mathematical solution to the general problem of multiple wavelengths. In order to determine all the diffusion coefficients of an n-component mixture, (n-1) beams of different wavelengths are required. Therefore, we can determine all the diffusion coefficients from the transient beam deflection measurements.Thursday, February 9, 2006
Seminar at 12:45 p.m.
OHE 122
Refreshments will be served after the seminar in HED Lobby
The Scientific Community is Cordially Invited
Location: Olin Hall of Engineering (OHE) - 122
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Materials Science Seminar
Fri, Feb 10, 2006 @ 02:15 PM - 03:30 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Fabrication and Characterization of
Nanoscale Hybrid Structures and DevicesJia Grace Lu
Department of Chemical Engineering and Materials Science
Department of Electrical Engineering and Computer Science
University of California, IrvineIn this talk, I will describe the research on the nano materials and hybrid structures currently undertaking in my group. By integrating bottom-up synthesis technique with top-down lithographic technique, various nanostructures are fabricated, and they are characterized by different methods such as TEM, SEM, XRD, photoluminescence, photoconductance, scanning surface potential microscopy, and electrical transport measurement. These nanostructures are used to build a range of electronic devices including field effect transistors (FET), chemical sensors, and single-electron transistors (SET). For example, individual ZnO nanowire FETs are implemented as highly sensitive chemical sensors for detection of NO2, NH3, CO toxic gases. Due to a Debye screening length comparable to the nanowire diameter, the electric field applied over the back gate electrode can significantly affect the sensitivity. A strong negative gate field is also found to efficiently refresh the sensors via an electrodesorption mechanism. As another example, spin dependent transport is studied in ferromagnetic SET devices with Co/Al2O3/Al nanoscale tunnel junctions. They exhibit typical single electron tunneling behavior including Coulomb blockade and gate modulation. Magnetoconductance measurements show bell-shaped I - H curves as a result of the direct influence of the magnetic field on the superconducting gap. In addition, the magnetic moment switching in the Co electrodes from parallel to antiparallel configurations give rises to a rich phenomenon of spin transport. Different transport mechanisms based on the spin accumulation effect and the Meservey-Tedrow effect will be presented. Brief Bio-Sketch:Dr. Lu received her dual B.S. degrees in Physics and Electrical Engineering from Washington University in 1992, M.S. and Ph.D. degrees in Applied Physics from Harvard University in 1993 and 1997, respectively. Currently she holds a joint appointment in the Department of Electrical Engineering and Computer Science and the Department of Chemical Engineering and Materials Science at UC Irvine. She had received the National Science Foundation Career Award in 2002 and the Presidential Early Career Award for Scientists and Engineers in 2004.
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Chemical Engineering Seminar
Thu, Feb 16, 2006 @ 12:45 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Cellular Membrane Materials as Motors: Optical Methods to Characterize Nanoelectromechanical PropertiesProfessor Bahman Anvari
Department of Bioengineering
Rice UniversityThe ability of cellular membranes to perform useful work is often ignored because they are relatively delicate and under many conditions deform easily. Yet, the membranes of living cells are poised to utilize the intense electric fields (> 10 MV/m) generated by the electrochemical gradients across them. For example, the ability of membranes to generate electrically-induced force is demonstrated in cochlear outer hair cells (OHCs) that are capable of producing rapid (> 50 kHz) movements, known as electromotility, a process required for normal hearing.
Using a novel experimental approach that combines optical trapping with voltage-clamping and fluorescence imaging, we have demonstrated that native biological membranes are capable of electrically-induced pico-Newton level force generation over a broad range of electrical excitation frequency (> 3 kHz). This electromechanical force is: (1) enhanced in presence of a specialized transmembrane protein, prestin, found in the OHCs; (2) affected by the amplitude and polarity of the transmembrane electrical potential; and (3) diminished in the presence of a specific anionic amphipathic agent, salicylate.
Our long-term objectives are to understand the molecular basis of electromotility, and investigate how membrane-based electromechanical coupling can be modulated in a controlled manner through changes in membrane physical properties and membrane-protein interactions. Characterizing the nanoelectromechanical properties of plasma membranes has the potential to not only lead to a better understanding of the hearing process and development of therapeutics for specific types of hearing loss, but also has relevance to a broad range of biological processes where membranes harness the energy in the transmembrane electric field, and to the development of biological nano-electromechanical systems with diagnostics and therapeutic applications.Thursday, February 16, 2006
Seminar at 12:45 p.m.
OHE 122
Refreshments will be served after the seminar in HED Lobby
The Scientific Community is Cordially Invited
Location: Olin Hall of Engineering (OHE) - 122
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Materials Science Seminar
Fri, Feb 17, 2006 @ 02:30 PM - 04:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Phase transitions in polyelectrolytes, polyampholytes and charged colloidsProf. A.Z. Panagiotopoulos
Dept. of Chemical Engineering
Princeton UniversityThis seminar starts with a brief historical overview of simulation studies of phase transitions in fluids dominated by coulombic interactions. It then summarizes recent work on modeling phase transitions in asymmetric ionic and charged polymer systems. The unifying characteristic of these fluids is the close interplay between microstructure and macroscopic properties and the existence of strong interactions or multiple relevant length scales. A fine-lattice discretization approach is used for the computations, combined with multihistogram reweighting. The fine-lattice approach allows close approximation of continuum systems with significant computational savings. For the size- and charge-asymmetric ionic systems we find that the critical parameters scale in a way contrary to the predictions of most integral equation theories. Systems with additional short-range interactions show a wealth of behavior including tricriticality, ionic criticality and conventional (non-ionic) criticality. Polyelectrolyte phase diagrams indicate that the existence of two separate length scales results in a finite critical density extrapolated to infinite chain length. Finally, mixtures of charged colloids and salts show non-monotonic dependence of the critical parameters on salt content and an interplay between the critical lines of the pure salt and colloid that can lead to discontinuous critical lines.Location: Grace Ford Salvatori Hall Of Letters, Arts & Sciences (GFS) - 116
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Biomolecular Engineering for Fun and Profit
Thu, Feb 23, 2006 @ 12:45 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Graduate SeminarBiomolecular Engineering for Fun
and ProfitDr. Huimin Zhao
Departments of Chemical and Biomolecular Engineering,
Chemistry, and Bioengineering,
Institute for Genomic Biology, and Center for Biophysics
and Computational Biology,
University of Illinois, Urbana ABSTRACTBiomolecules such as nucleic acids and proteins have been increasingly exploited for applications in medical, chemical, agricultural, and food industries. However, a major limitation in the applications of biomolecules is the existence of a functional gap between naturally occurring biomolecules and those required by specific practical settings. Thus, how to close this functional gap has become a première intellectual and engineering challenge. In this talk, I will discuss our recent work on the development of new biomolecular engineering tools and their applications. Specifically, I will discuss: (1) developing estrogen receptor based genetic switches for human gene therapy; (2) engineering a novel phosphite-dehydrogenase based NAD(P)H cofactor regeneration system, and (3) designing new biosynthetic pathways for synthesis of thermally stable energetic compounds. Thursday, February 23, 2006
Seminar at 12:45 p.m.
OHE 122
The Scientific Community is Cordially Invited
Location: Olin Hall of Engineering (OHE) - 122
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Carbon Nanotubes: The Tall Order
Fri, Feb 24, 2006 @ 02:45 PM - 04:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
A JOINT SEMINAR
DEPARTMENT OF PHYSICS AND ASTRONOMY
AND
MORK FAMILY DEPARTMENT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE PRESENTS
Professor P. M. Ajayan
Department of Materials Science and Engineering
Rensselaer Polytechnic Institute, N.Y.Carbon Nanotubes: The Tall Order
Carbon nanotubes are fascinating materials from the point of view of structure, form, growth and properties. The biggest challenge however is to assemble nanotubes into various architectures useful for specific applications. The talk will focus on the recent developments in our laboratory on the fabrication of carbon nanotube based architectures tailored for various applications. Various organized architectures of multiwalled and singlewalled carbon nanotubes can be fabricated using relatively simple vapor deposition techniques. The work in attaining control on the directed assembly of nanotubes on various platforms will be highlighted. Our efforts on the strategies of growth and manipulation of nanotube-based structures and in controllably fabricating hierarchically branched nanotube and nanotube-hybrid structures will be discussed. We have pursued several novel applications for these structures, for example, as nanostructured electrodes for sensors, electrical interconnects, unique filters for separation technologies, thermal management systems, multifunctional brushes, and polymer infiltrated thin film and bulk composites. A perspective of the field based on the work done by the author over a period of more than decade will be presented here with highlights from recent work and thoughts on future implications of the field.Friday, February 24, 2006, 3:00-4:00 PM
(Refreshments will be served at 2:45)
Location: SSL 150
**All first year materials science majors are required to attend**
Location: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: Petra Pearce
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High-Resolution Compositional Simulation of Multicontact Miscible Displacements
Mon, Feb 27, 2006 @ 01:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
GRADUATE SEMINARHigh-Resolution Compositional Simulation of Multicontact Miscible DisplacementsDr. Kristian Jessen
Stanford UniversityAbstract A significant portion of the existing hydrocarbon reserves are candidates for enhanced recovery processes. Miscible/near-miscible gas injection or water alternating gas injection processes hold the potential for significant improvement of recoveries relative to primary production and water flooding. The ultimate recovery of a miscible and near-miscible gas injection scheme is a complex function of the local displacement efficiency and global sweep efficiency. Successful performance evaluation of recovery processes based on numerical calculations requires, in part, high resolution in permeability heterogeneity and appropriate representation of the phase behavior and transport properties of the fluid system. Numerical simulation of these processes is challenging because the predicted displacement efficiency is very sensitive to numerical diffusion.
In this talk, I address the challenges related to compositional simulation of multicomponent multiphase flows. First, I demonstrate the shortcomings of conventional finite difference/volume (FD) simulation approaches in one dimension (1D), using a mix of analytical solutions, standard FD calculations and high order accurate FD calculations. I show that numerical artifacts have a fluid system specific impact on the prediction of the local displacement efficiency. This behavior is a direct result of the strong nonlinear coupling between flow and phase behavior. Next, I extend the analysis to 2D and 3D displacement processes. Physical dispersion is included in the model to delineate the grid resolution required to resolve the physics at a given simulation length scale. I present calculation examples for multicontact miscible gas/oil displacements and enhanced condensate recovery processes by gas injection/cycling. Finally, I conclude with a discussion of the future challenges and research directions in the field of compositional simulation.Monday, February 27, 2006
VKC 207
1:00 p.m.The Scientific Community is Cordially Invited
Location: Von Kleinsmid Center For International & Public Affairs (VKC) - 207
Audiences: Everyone Is Invited
Contact: Petra Pearce