Conferences, Lectures, & Seminars
Events for January
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L. L. Handy Colloquium Seminar
Thu, Jan 11, 2007 @ 12:45 AM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Smart Surfactants and Ligands in Pharmaceutical,
Environmental, and Energy Applications Professor Keith P. JohnstonDepartment of Chemical Engineering
The University of Texas at AustinABSTRACT Smart surfactants and ligands are being designed to (1) perform multiple functions, (2) achieve targeted activity at particular interfaces, and (3) be active at unusual interfaces, for example, in CO2. In pharmaceutical science, one of the key challenges is particle engineering of poorly water soluble drugs to achieve high bioavailability for oral and pulmonary administration. Increasingly, two goals are being pursued simultaneously: (1) control of particle nucleation and growth to achieve the desired particle morphology and (2) rapid wetting and dissolution, and in some cases high levels of supersaturation. Studies of fundamental thermodynamic, transport and interfacial mechanisms are leading to improvements in bioavailability in vivo.
Environmentally benign carbon dioxide-based emulsions may replace toxic organic solvents for pharmaceutical, chemical, materials, and microelectronics processing applications. Surfactants stabilize CO2-in-water emulsions or foams needed to control mobility in CO2-enhanced oil recovery, for producing 60 billion barrels of oil (approximately $6 trillion value). Nonionic methylated branched hydrocarbon surfactants emulsify up to 90% CO2 in water with polyhedral cells smaller than 10 microns, with the potential for excellent mobility control.
An emerging understanding of the role of surfactants in charging and stabilization mechanisms for colloids in low-permittivity solvents (dielect. const. < 5) will help advance a variety of applications including electrophoretic displays and electrophoretic deposition of nanocrystals to form superlattices. On the basis of novel experimental measurements for both hydrophilic and hydrophobic TiO2, a general mechanism is presented to describe particle charging in terms of preferential partitioning of cations and surfactant anions between the particle surface and reverse micelles in the bulk solvent. The design of smart surfactants and ligands for nano- and micron-sized emulsions and particle dispersions is in its infancy, and many new concepts will be developed for pharmaceutical, environmental, and energy applications.
Location: Olin Hall of Engineering (OHE) - 122
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Protein Mobility, Filtering, and Separation in Model Cell Membranes
Fri, Jan 12, 2007 @ 01:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Graduate SeminarProtein Mobility, Filtering, and Separation in Model Cell MembranesDr. Susan Daniel
Department of Chemistry
Texas A&M UniversityAbstract
Investigating how biomolecules behave in cell membranes gives us insight that can be used
to create better assays, sensors, and devices that mimic the cell surface. Applications for
these devices include rapid combinatorial analysis of drug targets, biosensors for toxin
detection, and proteomics research. Solid-supported lipid bilayers (SLBs) are an excellent
platform for mimicking the surface chemistry of cells. However, there are several drawbacks
to these platforms. First, proteins can lose their mobility in these systems, impairing their
function. Second, there is no good way to discriminate between analytes that bind to the
same surface ligand within these platforms. Third, separation, purification, and formation of
arrays of membrane species is difficult, impeding the progress of rapid combinatorial
assaying of membrane proteins.
Results will be presented on studies conducted to understand these issues and strategies to
overcome them. By investigating the behavior of protein-protein interactions on SLBs, we
found that protein-packing influences the point at which diffusion is arrested in these systems.
To improve binding specificity, we devised a system for size-selective discrimination of
protein analytes that bind to the same ligand, by incorporating poly(ethylene glycol) (PEG)
lipopolymers into SLBs. Using our platform, we were able to achieve discrimination of
several orders of magnitude. Finally, we developed a technique to separate membrane
species within an SLB: bilayer chromatography. Results will be presented that show our
separation method is sensitive enough to differentiate isomers of dye-labeled lipids and is
currently being extended to the separation of membrane proteins.
Friday, January 12, 2007
1:00 p.m.
HED 116
The Scientific Community is Cordially Invited to Attend.Location: Hedco Pertroleum and Chemical Engineering Building (HED) - 116
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Materials Science Seminar - Microbial fuel cell operation for electricity generation
Fri, Jan 12, 2007 @ 02:45 PM - 04:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Microbial fuel cell operation for electricity generationZhen HeDepartment of Energy, Environmental and Chemical Engineering
Washington University in St. LouisWe have developed upflow microbial fuel cells (UMFC) that simultaneously can clean wastewater and produce electricity. By sufficiently utilizing the inner volume of the anode and minimizing the space between electrodes the power output of the UMFC was improved from 3 to 25 W/m3. We are also working on harvesting electric energy from natural waters (e.g. river and ocean), with a novel design of a rotating cathode in a sediment microbial fuel cell to improve oxygen availability to the cathode. Finally, we have adopted a bacterium found in the normal human gut microbial community whose genome has been sequenced as a model anode biocatalyst to study its genomic variations using DNA chips. First year MASC students are required to attend.
Location: John Stauffer Science Lecture Hall (SLH) - 102
Audiences: Everyone Is Invited
Contact: Petra Pearce
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From Nanomedicine to Regenerative Medicine
Thu, Jan 18, 2007 @ 12:30 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
Inorganic-Biochemistry Seminar"From Nanomedicine to Regenerative Medicine"Dr. Ki-Bum LeeThe Skaggs Institute for Chemical Biology The Scripps Research InstituteThursday, January 18, 2007
12:30 PM
OHE Room 122Scientific Community is InvitedLocation: Olin Hall of Engineering (OHE) - 122
Audiences: Everyone Is Invited
Contact: Petra Pearce
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Electrophoresis of Highly Charged Colloids
Fri, Jan 19, 2007 @ 02:00 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
THE MORK FAMILY DEPARTMENT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE Presents a Joint Seminar with the
USC Quantum Information and Condensed Matter Physics
ByDr. Apratim ChatterjiUniversity of TorontoELECTROPHORESIS OF HIGHLY CHARGED COLLOIDSABSTRACTUsing computer simulations, the electrophoretic motion of a positively charged colloid (macroion) in an electrolyte solution is studied in the framework of the primitive model. In this model, the electrolyte is considered as a system of negatively and positively charged microions (counterions and coions, respectively) that are immersed into a structureless medium. Hydrodynamic interactions are fully taken into account by applying a hybrid simulation scheme, where the charged ions (i.e., ~ macroion and electrolyte), propagated via molecular dynamics (MD), are coupled to a Lattice Boltzmann (LB) fluid. In a recent electrophoretic experiment by Martin-Molina et al. [J. Phys. Chem. B 106, 6881 (2002)], it was shown that, for multivalent salt ions, the mobility µ initially increases with charge density reaches a maximum and then decreases with further increase of . The aim of the present work is to elucidate the behavior of µ at high values of . Even for the case of monovalent microions, we find a decrease of µ with . A dynamic Stern layer is defined that includes all the counterions that move with the macroion while subject to an external electrical field. We find that the number of counterions in the Stern layer, q0, is a crucial parameter for the behavior of µ at high values of . The previous contention that the increase in the distortion of the electric double layer (EDL) with increasing leads to the lowering of µ does not hold for high . In fact, we show that the deformation of the EDL decreases with increase of . The role of hydrodynamic interactions is inferred from direct comparisons to Langevin simulations where the coupling to the LB fluid is switched off. Moreover, systems with divalent counterions are considered. In this case, at high values of the phenomenon of charge inversion is found.January 19, 2007
2:00 PM
(Refreshments will be served at 1:45 PM)
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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SOME EXPERIMENTAL RESULTS ON ADIABATIC SHEAR BANDING
Fri, Jan 26, 2007 @ 02:45 PM
Mork Family Department of Chemical Engineering and Materials Science
Conferences, Lectures, & Seminars
THE MORK FAMILY DEPARTMENT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCEPRESENTS A SEMINAR
BYD. RittelFaculty of Mechanical Engineering Technion
32000 Haifa, IsraelSOME EXPERIMENTAL RESULTS ON ADIABATIC SHEAR BANDINGABSTRACT Assessing the dynamic mechanical properties of structural materials is an important stage of the design process of structures that must withstand various impacts. This data is mostly needed for numerical simulation purposes, when the dynamic response and eventual failure of a structure is to be evaluated. In this talk, we will address one specific dynamic failure mechanism, namely adiabatic shear banding. Adiabatic shear banding (ASB) is a catastrophic failure mechanism that may develop in certain ductile materials subjected to dynamic loading. The phenomenon itself consists of a narrow band of sheared material, in which the local temperature may reach a significant fraction of the melting temperature, as a result of thermomechanical coupling effects. As of today, there is an overwhelming disparity between analytical-numerical models related to ASB formation, and experimental evidence aimed at verifying a specific criterion or simply bringing physical evidence. This excludes of course the wealth of information related to microstructural aspects of ASB. The Dynamic Failure Laboratory at Technion has been investigating ASB formation from an experimental point of view. This talk will present new results on ASB formation in metals.
Three specific issues will be addressed, namely:1. A physical criterion for the onset of ASB formation
2. The influence of hydrostatic pressure on ASB formation
3. The influence of geometrical imperfections on ASB formationJanuary 26, 2006
2:45-3:30 PM
(Refreshments will be served at 2:30 PM)
SLH 102**ALL FIRST YEAR MATERIALS SCIENCE MAJORS ARE REQUIRED TO ATTEND**
Location: John Stauffer Science Lecture Hall (SLH) - 102
Audiences: Everyone Is Invited
Contact: Petra Pearce