School of Humanities and Sciences


Showing 301-310 of 370 Results

  • Daniel Stack

    Daniel Stack

    Associate Professor of Chemistry

    BioResearch in the Stack group focuses on the mechanism of dioxygen activation and the subsequent oxidative reactivity with primarily copper complexes ligated by imidazoles or histamines. Specifically, the group is interested in substrate hydroxylations and full dioxygen reduction. The remarkable specificity and energy efficiency of metalloenzymes provide the inspiration for the work. Trapping and characterizing immediate species, primarily at low temperatures, provide key mechanistic insights especially through substrate reactivity along with spectroscopic and metrical correlation to DFT calculations. Our objective is to move these efficient enzymatic mechanisms into small synthetic complexes, not only to reproduce biological reactivity, but more importantly to move the oxidative mechanism beyond that possible in the protein matrix.

    Daniel Stack was born, raised and attended college in Portland Oregon. He received his B.A. from Reed College in 1982 (Phi Beta Kappa), working with Professor Tom Dunne on weak nickel-pyrazine complexes. In Boston, he pursued his doctoral study in synthetic inorganic chemistry at Harvard University (Ph.D., 1988) with Professor R. H. Holm, investigating site-differentiated synthetic analogues of biological Fe4S4 cubanes. As an NSF Postdoctoral Fellow with Professor K. N. Raymond at the University of California at Berkeley, he worked on synthesizing new, higher iron affinity ligands similar to enterobactin, a bacterial iron sequestering agent. He started his independent career in 1991 at Stanford University primarily working on oxidation catalysis and dioxygen activation, and was promoted to an Associate Professor in 1998. His contributions to undergraduate education have been recognized at the University level on several occasions, including the Dinkelspiel Award for Outstanding Contribution to Undergraduate Education in 2003.

    Areas of current focus include:

    Copper Dioxygen Chemistry
    Our current interests focus on stabilizing species formed in the reaction of dioxygen with Cu(I) complexes formed with biologically relevant imidazole or histamine ligation. Many multi-copper enzymes ligated in this manner are capable of impressive hydroxylation reactions, including oxidative depolymerization of cellulose, methane oxidation, and energy-efficient reduction of dioxygen to water. Oxygenation of such complexes at extreme solution temperatures (-125°C) yield transient Cu(III) containing complexes. As Cu(III) is currently uncharacterized in any biological enzyme, developing connections between the synthetic and biological realms is a major focus.

    Surface Immobilization of Catalysts in Mesoporous Materials
    In redox active biological metal sites, the ligation environment is coupled tightly to the functional chemistry. Yet, the metal sites are also site-isolated, creating species that may only have a transient existence in a homogeneous solution. Site isolation of synthetic complexes can be achieved synthetically by supporting the metal complex on a solid matrix. Movement of these complexes into silica based materials or onto electroactive carbon electrodes represent a new direction for the group in the development of bio-inspired metal-based catalysts.

  • Tim Stearns

    Tim Stearns

    Professor of Biology

    Current Research and Scholarly InterestsWe use the tools of genetics, microscopy, and biochemistry to understand fundamental questions of cell biology: How are cells organized by the cytoskeleton? How do the centrosome and cilium control cell control cell signaling? How is cell division coordinated with duplication of the centrosome, and what goes wrong in cancer cells defective in this coordination?

  • Leonard Susskind

    Leonard Susskind

    Felix Bloch Professor of Physics

    BioLeonard Susskind is the Felix Bloch professor of Theoretical physics at Stanford University. His research interests include string theory, quantum field theory, quantum statistical mechanics and quantum cosmology. He is a member of the National Academy of Sciences of the USA, and the American Academy of Arts and Sciences, an associate member of the faculty of Canada's Perimeter Institute for Theoretical Physics, and a distinguished professor of the Korea Institute for Advanced Study.

    Susskind is widely regarded as one of the fathers of string theory, having, with Yoichiro Nambu and Holger Bech Nielsen, independently introduced the idea that particles could in fact be states of excitation of a relativistic string. He was the first to introduce the idea of the string theory landscape in 2003.

  • Yuri Suzuki

    Yuri Suzuki

    Professor of Applied Physics and, by courtesy, of Materials Science and Engineering

    Current Research and Scholarly InterestsHer interests are focused on novel ground states and functional properties in condensed matter systems synthesized via atomically precise thin film deposition techniques with a recent emphasis has been on highly correlated electronic systems:
    • Emergent interfacial electronic & magnetic phenomena through complex oxide heteroepitaxy
    • Low dimensional electron gas systems
    • Spin current generation, propagation and control in complex oxide-based ferromagnets
    • Multifunctional behavior in complex oxide thin films and heterostructures