Browsing Chemistry Faculty Research, Publications and Presentations by Title

Now showing items 153-172 of 233

  • Regioselective Substituent Effects upon the Synthesis of Dipyrrins from 2-Formyl Pyrroles 

    Regioselective Substituent Effects upon the Synthesis of Dipyrrins from 2-Formyl Pyrroles. Beh, M.H.R.; Figliola, C.; Lund, K-l. A.R.; Kajetanowicz, A.K.; Johnsen, A.E.; Aronitz, E.M.; Thompson, A. Can. J. Chem. 2018, 96, 779-784, special issue to honour Dalhousie’s 200th anniversary (NSERC). https://doi.org/10.1139/cjc-2017-0662
    The synthesis of symmetric α-free meso-H-dipyrrin hydrobromides from 5-H-2-formyl pyrroles was investigated. The self-condensation produces regioisomeric dipyrrins through the adoption of two mechanistic pathways. The key ...

  • Relating 139La Quadrupolar Coupling Constants to Polyhedral Distortion in Crystalline Structures 

    Relating 139La Quadrupolar Coupling Constants to Polyhedral Distortion in Crystalline Structures Alexander L. Paterson, Margaret A. Hanson, Ulrike Werner-Zwanziger, and Josef W. Zwanziger The Journal of Physical Chemistry C 2015 119 (45), 25508-25517 DOI: 10.1021/acs.jpcc.5b09122
    A broad series of crystalline lanthanum oxide-based materials has been investigated through high-field 139La solid state nuclear magnetic resonance (ssNMR) spectroscopy and ab initio density functional theory (DFT) ...

  • Reversible lithium insertion in catalytically graphitized sugar carbon 

    M.N. Obrovac, Xiuyun Zhao, L.T. Burke and R.A. Dunlap, Reversible Lithium Insertion in Catalytically Graphitized Sugar Carbon, Electrochem. Commun., 60 (2015), 221-224
    Highlights • First report of Li insertion in highly ordered catalytically derived graphite. • Fe catalyst combined with hard carbon precursors enable 1200 °C graphitization. • First report of highly ordered graphite ...

  • The Reversible Magnesiation of Pb (Preprint) 

    Published Version: Kalani Periyapperuma, Tuan T. Tran, M.I. Purcell and M.N. Obrovac, The Reversible Magnesiation of Pb, Electrochim. Acta, 165 (2015) 162-165. https://doi.org/10.1016/j.electacta.2015.03.006
    Sputtered Pb films have been found to reversibly alloy electrochemically with magnesium in Grignard based electrolytes. The voltage curve shows a single plateau at about 125 mV vs. Mg, corresponding to the formation of ...

  • Robust Synthesis of F-BODIPYs 

    Publisher's version: Beh, Michael; Douglas, Katherine; House, Kelsey; Murphy, Alexandra; Sinclair, Jackson; and Thompson, Alison. Robust Synthesis of F-BODIPYs. Org. Biomol. Chem. 2016, 14, 11473-11479. DOI: 10.1039/c6ob02238c
    F-BODIPYs are widely used in applications that rely upon their highly tunable optical properties. A protocol is established for the high-yielding synthesis of F-BODIPYs involving non-anhydrous reagents and not requiring ...

  • Scope and limitations in sulfur ylide mediated catalytic asymmetric aziridination of imines: use of phenyldiazomethane, diazoesters and diazoacetamides 

    Aggarwal, VK, M. Ferrara, CJ O'Brien, A. Thompson, et al. 2001. "Scope and limitations in sulfur ylide mediated catalytic asymmetric aziridination of imines: use of phenyldiazomethane, diazoesters and diazoacetamides." Journal of the Chemical Society-Perkin Transactions 1: 1635-1643.
    No abstract available.

  • Self-assembly of novel trimers using dipyrromethene ligands 

    Thompson, A., SJ Rettig, and D. Dolphin. 1999. "Self-assembly of novel trimers using dipyrromethene ligands." Chemical Communications: 631-632.
    Ligands comprising two dipyrromethene units linked at the beta-position have been used to prepare trimeric complexes with Zn-II and Co-II; the structure of the Zn-II complex is confirmed by X-ray analysis.

  • Si85Fe15Ox Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries 

    Yijia Liu, Michael Charlton, Jun Wang, J. Craig Bennett and M. N. Obrovac. Si85 Fe15 Ox Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries. J. Electrochem. Soc. (2021), 168 (11), 110521.
    The synthesis, microstructure and electrochemical properties of ball milled Si85Fe15Ox alloys with different oxygen contents are investigated. These materials combine the features of Si-M alloys (low irreversible capacity) ...

  • Sintered polymeric binders for Li-ion battery alloy anodes 

    T.D. Hatchard, R.A. Fielden and M.N. Obrovac, Sintered Polymeric Binders for Li-ion Battery Alloy Anodes, Can. J. Chem., 96 (2018) 765-770.
    The cycling performance in lithium half cells of Si alloy electrodes with polyvinylidene fluoride or polyimide binders were evaluated after the electrodes were cured at temperatures below and above the binder carbonization ...

  • Sodium distribution in sodium tellurite glasses probed with spin-echo NMR 

    Zwanziger, JW, JC McLaughlin, and SL Tagg. 1997. "Sodium distribution in sodium tellurite glasses probed with spin-echo NMR." Physical Review B 56(9): 5243-5249. doi:10.1103/PhysRevB.56.5243
    We present results on the spatial distribution of sodium cations in sodium tellurite glasses as a function of sodium oxide content, obtained using a spin-echo NMR experiment. Glasses were studied with sodium oxide content ...

  • Soft x-ray excited optical luminescence: Some recent applications 

    Hu, YF, KH Tan, PS Kim, P. Zhang, et al. 2002. "Soft x-ray excited optical luminescence: Some recent applications." Review of Scientific Instruments 73(3): 1379-1381.
    No abstract available.

  • Soft x-ray-excited luminescence and optical x-ray absorption fine structures of tris (8-hydroxyquinoline) aluminum 

    Naftel, SJ, P. Zhang, PS Kim, TK Sham, et al. 2001. "Soft x-ray-excited luminescence and optical x-ray absorption fine structures of tris (8-hydroxyquinoline) aluminum." Applied Physics Letters 78(13): 1847-1849.
    No abstract available.

  • Spherically Smooth Cathode Particles by Mechanofusion Processing 

    Lituo Zheng, Congxiao Wei, M. D. L. Garayt, Judy MacInnis, and M. N. Obrovac, Spherically Smooth Cathode Particles by Mechanofusion Processing, J. Electrochem. Soc., 166 (2019) A2924-A2927.
    Surface modification has been shown to be useful for improving the cycling performance of cathode materials. Typically hetero-compositional coatings are applied on cathode particle surfaces using methods, such as aqueous ...

  • Spin waves and quantum criticality in the frustrated XY pyrochlore antiferromagnet Er2Ti2O7 

    Ruff, J. P. C., J. P. Clancy, A. Bourque, M. A. White, et al. 2008. "Spin waves and quantum criticality in the frustrated XY pyrochlore antiferromagnet Er2Ti2O7." Physical Review Letters 101(14): 147205-147205. Copyright © 2008 American Physical Society.
    We report detailed measurements of the low temperature magnetic phase diagram of Er2Ti2O7. Heat capacity and time- of- flight neutron scattering studies of single crystals reveal unconventional low- energy states. Er3+ ...

  • Stabilizing NaCrO2 by Sodium Site Doping with Calcium 

    Lituo Zheng, J. C. Bennett, and M. N. Obrovac, Stabilizing NaCrO2 by Sodium Site Doping with Calcium, J. Electrochem. Soc., 166 (2019) A2058 - A2064.
    Layered cathode materials based on abundant, low cost raw materials have garnered interest in recent years. O3-type NaCrO2 is a promising cathode material as it offers decent energy density and is easy to synthesize. In ...

  • Step-wise synthetic approach is necessary to access g-conjugates of folate: folate-conjugated prodigiosenes 

    Despite the vast literature that describes reacting folic acid with a pharmacophore, this route is ineffective in providing the correct regioisomer of the resulting conjugate. We herein present a step-wise route to the ...

  • Structural and Electrochemical Investigation of FexSi1-x Thin Films in Li Cells 

    Zhijia Du, R. A. Dunlap and M. N. Obrovac, Structural and Electrochemical Investigation of FexSi1-x Thin Films in Li Cells, J. Electrochem. Soc., 163 (2016) A2011-A2016.
    FexSi1-x thin films with 0 ≤ x ≤ 0.46 have been prepared by combinatorial sputtering and their electrochemical properties have been studied in Li half-cells. X-ray diffraction showed that all of the films had an amorphous ...

  • Structural and electronic properties of protein/thiolate-protected gold nanocluster with "staple" motif: A XAS, L-DOS, and XPS study. 

    Reproduced from Simms, Gordon A., J. Daniel Padmos, and Peng Zhang. 2009. "Structural and electronic properties of protein/thiolate-protected gold nanocluster with "staple" motif: A XAS, L-DOS, and XPS study.." Journal of Chemical Physics 131(21): 2147031-214703/9, with the permission of AIP Publishing.
    No abstract available.

  • Structural principles and amorphouslike thermal conductivity of Na-doped Si clathrates 

    Tse, JS, K. Uehara, R. Rousseau, A. Ker, et al. 2000. "Structural principles and amorphouslike thermal conductivity of Na-doped Si clathrates." Physical Review Letters 85(1): 114-117. Copyright © 2000 American Physical Society.
    The postulated low thermal conductivity and the possibility of altering the electronic conductivity of metal-doped clathrates with semiconducting host elements have stimulated great interest in exploring these compounds ...

  • Structural principles and amorphouslike thermal conductivity of Na-doped Si clathrates (vol 85, pg 114, 2000) 

    Tse, JS, K. Uehara, R. Rousseau, A. Ker, et al. 2001. "Structural principles and amorphouslike thermal conductivity of Na-doped Si clathrates (vol 85, pg 114, 2000)." Physical Review Letters 86(21): 4980-4980. Copyright © 2001 American Physical Society.
    No abstract available.