Fall 2014 Seminars
September 1, 2014
September 8, 2014
September 15, 2014
September 22, 2014
September 26, 2014
**Special time 3:00 - 4:00**Ab initio electron dynamics at metal–semiconductor nano-interfaces
September 29, 2014
October 6, 2014
October 13, 2014
October 20, 2014
<Special Location!> Ruga Mechanics of Folding Atomic-Layer Nanostructures
October 27, 2014
Promoting and assessing student metacognition in physics
November 3, 2014
How do Student Evaluations of Instruction Relate to Students’ Conceptual Learning Gains?
November 7, 2014
<Special Day!!>Encapsulation of solutes in lipid vesicles: Origins of life considerations
November 10, 2014
Transdermal Therapeutic Systems: Structure, Function and Exelon(r) as a convincing example.
November 17, 2014
Effects of substrate on structural and electronic properties of laser-crystallized silicon films
November 24, 2014
Nitrogen Hydrides Towards Massive Star Forming Regions
December 1, 2014
Microgels as Chemical Sensors and Drug Delivery Vehicles
December 8, 2014
2D block copolymer films embedded in a 3D world
Andrew B. Croll
December 15, 2014
<Exam Week!> Elasticity-based mechanism for collective motion in natural and artificial swarms
Elasticity-based mechanism for collective motion in natural and artificial swarms.
Unaffiliated Research Scientist in Chicago supported by the National Science Foundation
and Visiting Scholar Applied Math Department
Monday, December 15, 2014, 3:00-4:00pm, Refreshments at 2:30.
221 South Engineering
Collective motion is one of the simplest forms of self-organization in systems of active components such as cell colonies, bird flocks, fish schools, or groups of autonomous robots. Its emergence in fluid-like swarms with aligning interactions has been the focus of much research activity. In this talk, I will introduce a different model for collective motion, consisting of self-propelled particles connected by linear springs without explicit aligning dynamics. In this system, a simple elasticity-based mechanism drives the particles to self-organize by cascading self-propulsion energy towards lower-energy modes. Given its ubiquity, this mechanism could play a relevant role in various natural and artificial swarms.
Spring 2015 Seminars
January 12, 2015
January 19, 2015
Martin Luther King, Jr. Day
January 26, 2015
February 2, 2015
February 9, 2015
<Presidents' Day> Engineering Persister-Specific Antibiotics with Synergistic Antimicrobial Functions
February 23, 2015
March 2, 2015
APS March Meeting
March 9, 2015
March 16, 2015
March 23, 2015
March 30, 2015
April 1, 2015
<Special Day and Location!!>Structure, Dynamics and Properties of Block Polymer Dispersions
April 6, 2015
April 13, 2015
April 20, 2015
April 24, 2015
April 27, 2015
May 4, 2015
May 5, 2015
<Special Day and Location!!>A Robust Nonlinear Block Copolymer Nanoreactor-Based Strategy to Monodisperse Hairy Nanocrystals with Precisely Controlled Dimensions, Compositions and Architectures
May 11, 2015
Structure, Dynamics and Properties of Block Polymer Dispersions
Dr. Frank S. Bates
Regents Professor and Head, Department of Chemical Engineering and Materials Science, University of Minnesota
<Special Time!!>Wednesday, April 1, 2015, 3:00-4:00pm (refreshments served 2:30).
<Special Location!!>271 Batcheller Technology Center
Block copolymers belong to a broad class of amphiphilic compounds that includes soaps, lipids and nonionic surfactants. These macromolecules assemble into micelles with molecular dimensions on the order of 5 to 50 nm in size when mixed with excess solvent that preferentially solvates one block type. This presentation will explore two different aspects of block copolymer micelle formation. The fundamental thermodynamic and kinetic factors that control micelle shape and dynamics will be discussed based on small-angle x-ray and neutron scattering (SAXS and SANS) experiments and cryogenic transmission and scanning electron microscopy results. Although the structural features displayed by amphiphilic block copolymers resemble those associated with the self-assembly of lipids and simple surfactants (e.g., spherical and cylindrical micelles and vesicles) a macromolecular architecture leads to remarkably different dynamic properties, linked to a vanishingly small critical micelle concentration. As a consequence, molecular exchange is rapidly extinguished with increasing molecular weight resulting in non-ergotic behavior. These concepts have been exploited in developing a recently commercialized technology that provides immense improvements in the fracture toughness of thermosetting epoxy plastics, which also will be described.
A Robust Nonlinear Block Copolymer Nanoreactor-Based Strategy to Monodisperse Hairy Nanocrystals with Precisely Controlled Dimensions, Compositions and Architecture.
Dr. Zhiqun Lin
Professor, School of Materials Science and Engineering, Georgia Institute of Technology
<Special Time!!> Tuesday, May 5, 2015, 3:00-4:00pm (Refreshments will be served at 2:30).
<Special Location!!>271 Bachellor Technology Center
Nanocrystals exhibit a wide range of unique properties (e.g., electrical, optical, and optoelectronic) that depend sensitively on their size and shape, and are of both fundamental and practical interest. Breakthrough strategies that will facilitate the design and synthesis of a large diversity of nanocrystals with different properties and controllable size and shape in a simple and convenient manner are of key importance in revolutionarily advancing the use of nanocrystals for a myriad of applications in lightweight structural materials, optics, electronics, photonics, optoelctronics, magnetic technologies, sensory materials and devices, catalysis, drug delivery, biotechnology, and among other emerging fields. In this talk, I will elaborate a general and robust strategy for crafting a large variety of functional nanocrystals with precisely controlled dimensions (i.e., plain, core/shell, and hollow nanoparticles) by capitalizing on a new class of unimolecular star-like block copolymers as nanoreactors. This strategy is effective and able to produce organic solvent-soluble and water-soluble monodisperse nanoparticles, including metallic, ferroelectric, magnetic, luminescent, semiconductor, and their core/shell nanoparticles, which represent a few examples of the kind of nanoparticles that can be produced using this technique. The applications of these functional nanocrystals in energy-related applications (i.e., solar cells and photocatalysis) will also be discussed.