Past Seminars & Events
Thursday, Sept. 14, 2023, 9:45 a.m. through Thursday, Sept. 14, 2023, 11:15 a.m.
331 Smith Hall
The Story of Light and Single Molecules: From Spectroscopy in Solids, to Super-Resolution Nanoscopy in Cells and Beyond
The optical detection of single molecules has provided a new view into the nanoscale. Since ensemble averaging is removed, each single molecule can act as a reporter of not only its position, but also local information about the nearby environment. One key application is super-resolution microscopy, which enables biological objects and material structures to be observed with resolutions down to tens of and below. Examples range from protein superstructures in bacteria to bands in axons to details of the shapes of amyloid fibrils, cell surface sugars, protein superstructures in the primary cilium, and much more. For super-resolution imaging in thick cells, a new tilted light sheet design makes use of optical engineering methods which alter the fundamental way in which a microscope works, providing a simple, useful 3D microscope. Low temperature single-molecule imaging provides much improved localization precision in order to complement cryo-electron tomography studies. Even coronavirus RNA in an infected mammalian cell forms amazing cluster-like structures which are reminiscent of the galaxies from modern telescopes. Combining super-resolution imaging of a static structure with time-dependent 3D tracking of other biomolecules provides a powerful view of cellular dynamics. While not all of these topics can be covered, they serve to illustrate the continuing richness of the field.
W. E. Moerner
W. E. Moerner is the Harry S. Mosher Professor of Chemistry, Applied Physics, Biophysics, and Molecular Imaging at Stanford University. He is a pioneer in the fields of single molecule spectroscopy, super-resolution microscopy, and quantum optics including single-molecule biophysics in cells; nanophotonics of metallic nanoantennas; and photoactive polymer materials. Major milestones include first room-temperature single-molecule source of single photons, 3-D studies of single molecules diffusing in gels, observation of blinking and switching in single GFP molecules, pumping of single molecules with whispering gallery modes of microspheres, and beam fanning and self-pumped phase conjugation in new extremely high gain photorefractive polymers. He is the 2014 Nobel Laureate in Chemistry for the development of super-resolved fluorescence microscopy, in addition to awards including the Wolf Prize in Chemistry, the Peter Debye Award in Physical Chemistry, the Earle K. Plyler Prize for Molecular Spectroscopy, and the Irving Langmuir Prize in Chemical Physics.
Monday, Sept. 11, 2023, 4 p.m. through Monday, Sept. 11, 2023, 5 p.m.
331 Smith Hall
Creating new electron-deficient types of functional dyes that are potentially useful as electron acceptors in solar cells
We have developed synthetic protocols for the preparation of several classes of electron-deficient functional dyes that have a first reduction potential close to the traditional fullerenes. These include (i) functionalization of BODIPY core at meso-position; (ii) creation and functionalization of BOPHY platform; (iii) selective synthesis of 2-pyridone-BODIPYs; (iv) creation of electron-deficient “Manitoba Dipyrromethene” (MB-DIPY) chromophores and (v) discovery of hybrid β-isoindigo-aza-DIPY systems (Figure 1).
Victor N. Nemykin
Professor Victor Nemykin is currently a Head of the Department of Chemistry at the University of Tennessee - Knoxville. He was born and raised in Ukraine, where he received an undergraduate degree from Kyiv State University and a Ph.D. from the Institute of General and Inorganic Chemistry (1995). After JSPS (1998-2000) and Duquesne University postdoctoral positions, he was a faculty at the University of Minnesota - Duluth (2004-2016) and Professor and Head of the Department of Chemistry at the University of Manitoba (2016-2020). He co-authored more than 265 research papers, reviews, and book chapters.
Thursday, Sept. 7, 2023, 9:45 a.m. through Thursday, Sept. 7, 2023, 11:15 a.m.
331 Smith Hall
Professor Philippe Buhlmann
Department of Chemistry
University of Minnesota
Electroanalytical Sensing with Polymeric Receptor-Doped Sensor Membranes
Selective electrodes for the detection of ions in liquids such as human body fluids or environmental waters are highly sensitive and selective analytical tools that offer a variety of advantages, such as simplicity of measurement, high analysis throughput, rapid detection, continuous on- line monitoring, and low cost of analysis. While such sensors are used in clinical laboratories for billions of measurements every year, applications in continuous health monitoring, the food industry, and environmental sciences still pose challenges. The Buhlmann group has contributed to the development of such sensors with new design principles and quantitative theory as well as the introduction of new materials to meet the needs of real life applications. This talk will address the long-term sensor stability of wearable and implantable sensors, challenges and opportunities of calibration-free measurements, miniaturization and low-cost design for point-of-care analysis, and—in view of long-term monitoring in the human body and the environment—robust design and resistance to chemical and biological fouling.
Professor Philippe Buhlmann has been a member of the University of Minnesota Department of Chemistry since 2000. His group’s research is interested in the use of molecular recognition for chemical sensing. Their chemical sensor development focuses on new receptors that bind analytes of interest with high selectivity, novel strategies to obtain very low detection limits, and perfluoropolymers that permit long- term monitoring and eventually the implantation into the human body. Buhlmann’s research also pursues new ways to chemically modify metal and carbon nanotube tips, and use them in scanning tunneling microscopy for chemically selective imaging with molecular resolution.
Over the past two decades, his dedication to research and mentorship have earned the 3M/Alumni Professorship and the Distinguished University Teaching Professorship. Earlier this year, he received the American Chemical Society’s 2023 Minnesota Award “for being an international authority in the field of ion-selective electrodes and related research fields, for his outstanding work in volunteering for MN ACS, for being an outstanding research advisor, mentor, scholar and teacher AND having a positive impact on the lives of many graduate students in his own research group, in the Chemistry Department, and beyond.”
Wednesday, Sept. 6, 2023, 4:30 p.m. through Wednesday, Sept. 6, 2023, 5:30 p.m.
331 Smith Hall
Engineering fluid-fluid interfaces through processing and multicomponent adsorption
Systems involving deformable interfaces between immiscible fluids offer a significant challenge for materials design and processing. Static interfacial/surface tension is often the only parameter considered in the design of systems with fluid-fluid interfaces. In foams, emulsions, blends, sprays, droplet-based microfluidic devices and many other applications, the dynamic nature of surface active species and deformation of interfaces requires a more detailed characterization of the interfacial transport, dynamic interfacial properties and interfacial structure. Macroscopic properties and the ability to tune and control phenomena requires an improved understanding of the time-dependent properties of the interfacial tension and interfacial mechanics. We have developed tools and approaches to quantify the impact of surface active species, particularly polymeric species, on interfacial behavior. Surfactant-nanoparticle complexes, polymer-surfactant aggregates and proteins (sequence specific polymers) show the potential of interfacial processing in controlling interfacial properties. The use of sequential adsorption, differences in transport timescales and variability in reversibility of different species allows interfaces to be engineered. This talk will provide the motivation to use microscale interfaces for efficient analysis of complex interfacial phenomena and how that relates to the material properties of interface-dominated materials
Professor Lynn Walker
Prof. Lynn Walker received her B.S. degree from the University of New Hampshire and a Ph.D. from the University of Delaware, both in chemical engineering. Prior to joining CEMS, she was at Carnegie Mellon University in Chemical Engineering and both Chemistry (by courtesy) and Materials Science & Engineering (by courtesy). She was an NSF International Postdoctoral Fellow at the Katholieke Universiteit in Leuven, Belgium before joining CMU in 1997. She has held visiting faculty positions at the Polymer IRC in Leeds, UK, Chemical Engineering at UCSB, and held the Piercy Visiting Professorship at the University of Minnesota. Her research focuses on quantifying the coupling between flow behavior and flow-induced microstructure in complex fluids. Currently her research focuses in two directions: quantifying the influence of flow on self-assembled nanostructures and controlling transport to complex fluid-fluid interfaces. She recently took the role of Perspectives Editor for AIChE Journal, served as Editor-in-Chief of Rheologica Acta and serves on the editorial boards of the Journal of Rheology, and Journal of Non-Newtonian Fluid Mechanics. She is a fellow of the American Institute of Chemical Engineers, the Society of Rheology, and the American Physical Society (DSOFT).
Thursday, Aug. 24, 2023, 11 a.m. through Thursday, Aug. 24, 2023, Noon
231 Smith Hall
The NSF Center for Sustainable Polymers is hosting Nathaniel Lynd, Associate Professor, Department of Chemical Engineering at the University of Texas at Austin for a seminar from 11:00 – 12:00 P.M. in Smith 231 on Thursday, August 24, 2023.
The Lynd Group at UT Austin carries out fundamental and applied research in polymer science guided by the principles of simplicity, sustainability, and relevance to key technological challenges in chemical engineering for the 21st century in energy, environment, security, and materials for healthcare. Synthesis is the primary tool that the group uses to answer fundamental questions, and bring to bear in applied research projects. However, modeling efforts may be used to facilitate materials design, and to provide context for the interpretation of data. Particularly, the Lynd Group is engaged in research efforts that create and utilize new functional and reactive polyether materials and block polymers. Newer work is built on a foundation of novel techniques for advanced copolymer structure determination and detailed mechanistic understanding which facilitate the compositional control of structure-property-processing relationships.
Thursday, July 13, 2023, 9:45 a.m. through Thursday, July 13, 2023, 11:15 a.m.
402 Walter Library
University of Florida
Developing a versatile contrathermal Cope rearrangement platform for enantioselective synthesis
The Cope Rearrangement is a classic transformation of value to modern organic synthesis. Certain substrates classes have been well developed due to their ready availability and generally favorable energetic profiles. Conversely, 3,3-dicyano-1,5- dienes have been overlooked. We have been exploring 3,3-dicyano-1,5-dienes and have uncovered strategies to improve their energetic profiles in general ways that impact their applicability to complex molecule synthesis. We have also uncovered strategies for controlling absolute stereochemistry for this class of Cope substrate. This seminar will focus on how the marriage of fundamental and applied research has led to a diversifiable platform for Cope rearrangement-centered method development, (enantioselective) catalysis, target and analog synthesis, and other direct and tangentially related studies.
Thursday, May 25, 2023, 1:30 p.m. through Thursday, May 25, 2023, 4:30 p.m.
Thomas H. Swain Room
McNamara Alumni Center
200 SE Oak St, Minneapolis, MN
Save the date for a gathering and poster session to honor Prof. Wayne Gladfelter's contributions and legacy in our department and beyond. Gladfelter group alumni will present posters from their career paths since leaving the university. Some have spent their entire career at one company or college, while others moved to work with start-ups or even to careers outside of science altogether. All members of the Chemistry community are welcome to join Prof. Gladfelter and his group, chat with alums about career paths, and enjoy hors d'oeuvres.
Wayne Gladfelter has been a member of the UMN Chemistry faculty for more than 40 years. Over the past four decades, Gladfelter has shown unending dedication in his service to the departmental community and to his research. In 1999, Gladfelter was appointed chair of the Department of Chemistry, a position he held for six years. Shortly after stepping down as department chair, Gladfelter served as the college’s associate dean of Academic Affairs. He has advised more than 50 doctorate students and, with them, has co-authored more than 250 papers. He is one of the college’s Distinguished Professors honored for his contributions to teaching and scholarly research, and commitment to the college.
Wednesday, May 24, 2023, 10 a.m.
101 Walter Library
Professor Alex Jordan
Department of Engineering
University of Wisconsin-Stout
Rheological Measurements and Modelling in Polymer Processing
The world of polymer processing lies at the intersection of materials science, transport phenomena, fluid mechanics, controls, and economics. The undergraduate American university education model teaches these topics as “stand alone” courses, often disconnected from one another due to time and logistical constraints. At the post-graduate level, students are trained to develop a hypothesis, formulate a set of experiments, master experimental techniques, and perform statistical analysis to draw conclusions about their original hypothesis; resulting in a world-class knowledge in a singular topic. We will use three vignettes, each centered on a different processing technique, to demonstrate how you can implement your university training to contribute to the industrial polymer processing world.
Alex Jordan received his Ph.D. in Macromolecular Science and Engineering at Case Western Reserve University in 2016. While working for Prof. LaShanda Korley he utilized multilayer coextrusion as a technology to create non-woven fiber structures and an in situ method to fabricate fiber reinforced hydrogel structures. After defending his dissertation, he began work as a postdoctoral fellow at the University of Minnesota with Profs. Chris Macosko and Frank Bates studying interfacial phenomena in polyolefin blends and multilayer films. He moved to the University of Wisconsin – Stout as an Assistant Professor of plastics engineering in 2018. As a professor at a primarily undergraduate institution (PUI), he teaches foundational courses in polymer materials science and processing as well as upper level specialty courses in extrusion, thermoforming, and blow molding. He maintains his research interest in polymer rheology and processing through industrially sponsored projects and by mentoring senior undergraduate students during their year-long capstone experience.
Tuesday, May 2, 2023, 9:45 a.m. through Tuesday, May 2, 2023, 11:15 a.m.
331 Smith Hall
Department of Chemistry
University of Minnesota
Photochemistry: Advancing our understanding of molecules and materials upon electronic excitations
Understanding the complex photochemical behaviors of molecules and materials is essential, not only for fundamental interests in controlling the chemical reactions, but also numerous practical applications such as optoelectronic materials and quantum materials. The process of matter-light interaction is highly non-equilibrium and ultrafast, making it difficult to directly monitor these processes experimentally. Therefore, computer simulation plays a critical role in understanding the behaviors of molecules and materials upon excitations. Revealing the photochemical and photophysical processes from an atom-by-atom perspective will help us design the next generation of optoelectronic materials. And ultimately achieve our goals, such as controlling chemical reactions and designing highly cost-effective solar materials. In this talk, I will introduce you a hierarchy of electronic structure theories and nuclear dynamics algorithms that we have developed over the years. These methods go beyond the state-of-the-art, and therefore can simulate photochemical processes more efficiently and accurately. Additionally, I will highlight some of the successful applications of our methods, ranging from optoelectronic materials to molecular photochemical reactions.
Yinan Shu is currently a research associate in Prof. Donald G. Truhlar’s group at University of Minnesota. Prior to working with Prof. Truhlar, he was a Ph.D. candidate in Prof. Benjamin G. Levine’s group at Michigan State University. His research focuses on various topics within theoretical and computational chemistry, including electronic structure theory, nonadiabatic dynamics, material science, chemical reactions, and machine learning. He has received 2020 ACS Phys Young Investigator Award (ACS Division of Physical Chemistry), 2020 Robin Hochstrasser Young Investigator Award (Chemical Physics, Elsevier), and 2021 Spring Wiley Computers in Chemistry Outstanding Postdoc Award (ACS Division of Computers in Chemistry).
Thursday, April 27, 2023, 2:45 p.m. through Thursday, April 27, 2023, 4:45 p.m.
Graduate students and postdoctoral associates will present 15 minute presentations on an area of their research. Click on the event to see the full flash talk schedule.