Events Archive

Friday, January 31, 2020 - 3:10pm

Peter Sushko

Peter Sushko

Pacific Northwest National Lab

(Winter)

Friday, January 31, 2020 - 1:10pm

Steven Zimmerman

University of Illinois - Urbana-Champaign

(Zhao)

Wednesday, January 29, 2020 - 4:10pm to 5:00pm

Chris HanesAs you are aware, mental health is very important to have a safe and productive study and work environment. Unfortunately, self-care and mental health are often neglected. To stress the importance of mental health, we will have a presentation from the Director of Student Counseling Services at Iowa State, Chris Hanes, on the following topic:

Friday, January 24, 2020 - 3:10pm

Lauren Webb

Lauren Webb

Department of Chemistry, The University of Texas at Austin

(VanVeller)

Abstract:  Lipid bilayer membranes are complex, dynamic, and functional structures composed of a wide diversity of lipids, proteins, small molecules, and water organized in heterogeneous domains through noncovalent interactions. The structure and motion of these molecules generate large electric fields within the interior of the membrane that are critical to membrane structure and function.  Here, we describe how vibrational spectroscopy of unnatural nitrile chromophores places throughout the membrane structure is used to measure electrostatic fields in peptides intercalated in free-standing lipid bilayer membranes of increasing chemical complexity.  In combination with electrodynamics simulations, these experiments highlight how common small molecules such as cholesterol dramatically affect membrane structure and dynamics through large changes to membrane electric fields.  

Friday, January 24, 2020 - 1:10pm

Nancy Pleshko

Nancy Pleshko

Temple University

Society for Applied Spectroscopy (SAS) Student Chapter

Wednesday, January 15, 2020 - 4:10pm

Thiel Group: Michael Manley's student seminar.

Friday, January 10, 2020 - 1:00pm

Smita Patnaik Final Oral Sadow Group

Tuesday, January 7, 2020 - 10:00am

Benjamin Kosieradzki Final Oral Kraus Group

Thursday, December 12, 2019 - 5:00pm

It’s that time of the year… GSLC Presents: 

THE FOURTH ANNUAL CHILI COOK-OFF! 

What does it cost? Free for chemistry graduate students, faculty and staff who attend! 

For those competing, bring your chili for a chance to be immortalized on the plaque in 1605 Gilman Hall! We also will be giving a Hy-Vee gift card! 

Friday, December 6, 2019 - 3:10pm

Facundo Fernandez

Facundo Fernandez

Georgia Institute of Technology

(Lee)

Abstract

he highly dynamic nature of metabolites and their abundances makes metabolomics a powerful endpoint of the ‘omics’ cascade, yielding a molecular profile that is closest to the physiological phenotype. Metabolomic profiles are therefore sensitive to subtle perturbations observed in early disease stages or disease progression, which may be difficult to detect at the proteome or transcriptome levels. Human diseases are multi-factorial in nature, and studying small parts of their associated molecular changes is generally insufficient for understanding the full spectrum of disease phenotypes.

The metabolome is the total collection of biologically-active small molecules with molecular weights lower than about ~1.5 kDa in an organism. This includes endogenous molecules that are biosynthesized by metabolic networks in “primary metabolism”, specialized “secondary metabolite” signaling or defense molecules, molecules derived from diet or environmental exposures (the exposome), and molecules derived from the biosynthetic interactions with associated microbes (the microbiome). Metabolomics can either be “targeted” to a set of known compounds, for example certain lipids, or “non-targeted”, which attempts to detect and relatively quantify as many metabolites as possible.

The vast chemical diversity of the metabolome (lipids, sugars, amino acids, etc.), and its wide dynamic range (mM to fM) implies that no single analytical method can adequately profile all metabolites in one metabolomics experiment. Along these lines, the “fusion” of mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR) is emerging as one of the most powerful avenues to increase metabolome coverage. Nested separations that work in a time frame compatible with mass spectrometry, such as those performed by ion mobility, are also playing a key analytical role in metabolomics as a way of increasing peak capacity, and identifying metabolites through ion mobility collision cross section measurements. Further, localization of metabolites at the tissue level with imaging mass spectrometry experiments, allows linking their abundance with changes observed in biofluids. In this seminar, I will highlight progress along these various fronts, with emphasis on the detection, screening and treatment of complex diseases such as prostate and ovarian cancer, and cystic fibrosis.

Friday, December 6, 2019 - 1:10pm

Julia Chan

Julia Chan

The University of Texas at Dallas

(Zaikina)

The discovery and characterization of novel intermetallic compounds is important for broadening the understanding of structure-property relationships of magnetic materials. Our current research interests in superconductivity and unusual magnetism rely heavily on the intimate relationship between structure and physical properties. Likewise, the determination of anisotropic physical properties from high quality single crystals is vital in probing the intrinsic electrical and the competing magnetic interactions to understand the chemistry and physics of these materials. The discovery of novel magnetic and electronic properties in low-dimensional materials has led to the pursuit of hierarchical materials with specific substructures. Low-dimensional solids are highly anisotropic by nature and show promise in new quantum materials leading to exotic physical properties not realized in three dimensional materials.  In this talk, I will highlight the crystal growth, characterization, and properties of germanides and stannides and layered antimonides and the potential for compounds in reduced dimensions.

Friday, November 22, 2019 - 3:00pm

William Bradley, Final Oral, Kraus Group

Thursday, November 21, 2019 - 4:30pm

Justin Mark Final Oral Exam Kovnir Group

Tuesday, November 19, 2019 - 4:00pm

Zhuoran Wang Final Oral Pruski Group

Tuesday, November 19, 2019 - 2:10pm

Come learn strategies for writing successful grant proposals from a panel of expert grant writers, including our own Dr. Robbyn Anand!Anand

Tuesday, November 19, 2019 - 9:00am

Abhishek Kadam Final Oral Stanley Group

Monday, November 18, 2019 - 9:00am

Likun Duan Final Oral Zhao Group

Friday, November 15, 2019 - 1:10pm

Zachary Ball

Zachary Ball

Department of Chemistry, Rice University

(VanVeller)

Chemists are fascinated by metalloenzymes and their chemistry. The reactivity and selectivity of enzyme processes would be powerful practical advances if harnessed in designed transition-metal catalysts. But designing enzyme-like catalysts from scratch has proven exceedingly challenging. Substrate selectivity in polyfunctional environments and highly reactive intermediates incompatible with the bulk aqueous media are properties that are typically too complex and challenging to replicate in simplified, designed systems. Our own efforts have taken advantage of diverse concepts, such as molecular recognition, biomimetic assembly, and structure–function relationships to pursue new methods for site-selective chemistry.

Friday, November 8, 2019 - 3:10pm

Clifford Russell Bowers

Clifford Russell Bowers

Department of Chemistry, University of Florida

(Huang)

Nuclear spin singlet-states are attracting a lot of attention nowadays because they can significantly extend the useable lifetime of hyperpolarization. Singlet order decays more slowly than ordinary magnetization because the former is protected from the intra-pair dipole-dipole relaxation mechanism. Singlet-triplet imbalance (STI), which refers to the population differential between the singlet and triplet manifolds for a pair of strongly coupled spin-1/2 nuclei, can be prepared directly from parahydrogen, the singlet spin isomer of dihydrogen that is easily generated by cooling the gas in the presence of an ortho-para conversion catalyst. With perfect magnetic equivalence and isolation, the parahydrogen singlet is the quintessential long-lived state with a lifetime of many weeks. The transformation of singlet order into observable Zeeman order can be achieved by symmetry breaking chemistry.1 The key requirement is pairwise addition with retention of inter-pair spin-spin coupling. This talk will survey some highlights from our recent research utilizing heterogeneous catalysis to convert dihydrogen STI into magnetization on various target molecules in gases and solution. One of the main challenges that needs to be overcome is the fast diffusion of H ad-atoms that is typically observed on the catalytically active metal surfaces. We show that through rational design of heterogeneous catalysts, significant improvements can be made in the efficiency of the singlet-to-magnetization transformation.2-3 Three examples are presented: ultra-low loadings of Pt on shaped cerium oxide nanocrystal supports, PtSn intermetallic nanoparticles for hyperpolarization of water and alcohols, and certain other bimetallic combinations that have delivered substantially higher performance than monometallic nanoparticle catalysts. Lastly, a new approach utilizing heterogeneous catalysis for the continuous-flow synthesis of symmetric and pseudo-symmetric parahydrogen adducts hosting long-lived states will be presented.

Acknowledgements: NSF grants CHE-1808239 (CRB and WH), CBET-1933723 (HH-W and CRB) and the NHMFL-UCGP which is supported by the National Science Foundation Cooperative Agreement No. DMR-1644779 and the State of Florida.

1. CR Bowers, DP Weitekamp, PRL, 1986; CR Bowers, DP Weitekamp, JACS, 1987

2. Evan Wenbo Zhao, Raghu Maligal-Ganesh, Yong Du, Tommy Yunpu Zhao, James Collins, Tao Ma, Lin Zhou, Tian-Wei Goh, Wenyu Huang, Clifford R Bowers - Chem, 2018

3. Evan W Zhao, Raghu Maligal‐Ganesh, Chaoxian Xiao, Tian‐Wei Goh, Zhiyuan Qi, Yuchen Pei, Helena E Hagelin‐Weaver, Wenyu Huang, Clifford R Bowers -Angew. Chem. 2017

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