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Faculty Publications

2007

Chemistry

Articles 1 - 20 of 20

Full-Text Articles in Physical Sciences and Mathematics

1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Kis(Trifluoro­Meth­Yl)- 1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Hydro­(C60-IH)[5,6]Fullerene, Natalia B. Shustova Prof. Dr., O.P. Anderson, O. V. Boltalina, S. H. Strauss, I. E. Kareev Nov 2007

1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Kis(Trifluoro­Meth­Yl)- 1,3,7,10,14,17,21,28,31,42,52,55-Dodeca­Hydro­(C60-IH)[5,6]Fullerene, Natalia B. Shustova Prof. Dr., O.P. Anderson, O. V. Boltalina, S. H. Strauss, I. E. Kareev

Faculty Publications

The title compound, C72F36, is one of four isomers of C60(CF3)12 for which crystal structures have been obtained. The fullerene mol­ecule has an idealized Ih C60 core with the 12 CF3 groups arranged in an asymmetric fashion on two ribbons of edge-sharing C6(CF3)2 hexa­gons, a para–meta–para–para–para–meta–para ribbon and a para–meta–para ribbon, giving an overall pmp 3 mp,pmp structure. There are no cage Csp 3 …

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Rheology Of Tin Fluorophosphate Glass/Polyamide 12 Hybrids In The Low Concentration Regime, Kevin Urman, Thomas Schweizer, Joshua U. Otaigbe Nov 2007

Rheology Of Tin Fluorophosphate Glass/Polyamide 12 Hybrids In The Low Concentration Regime, Kevin Urman, Thomas Schweizer, Joshua U. Otaigbe

Faculty Publications

Phosphate glass (Pglass)/polymer hybrids are a unique material class that promises to help fulfill the growing need for new advanced materials. Rheological investigations into Pglass/polyamide 12 hybrids have shown a strong dependence on temperature and composition. Strong negative deviations from the log-additivity rule are also observed for these materials as well as a reduction in the activation energy for viscous flow. Hybrids containing < 2 vol. % Pglass are theologically simple fluids that display temperature independence in plots of storage modulus versus loss modulus. Hybrids containing >= 2 vol. % Pglass are rheologically complex and do not obey the time-temperature superposition principle. Through application of Han plots, we identified a structural change that occurs in hybrids containing >= 2 vol. % Pglass at …

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Structural Characterization Using The Multiple Scattering Effects In Grazing-Incidence Small-Angle X-Ray Scattering, Byeongdu Lee, Chieh-Tsung Lo, P. Thiyagarajan, Dong R. Lee, Zhongwei Niu, Qian Wang Oct 2007

Structural Characterization Using The Multiple Scattering Effects In Grazing-Incidence Small-Angle X-Ray Scattering, Byeongdu Lee, Chieh-Tsung Lo, P. Thiyagarajan, Dong R. Lee, Zhongwei Niu, Qian Wang

Faculty Publications

The multiple scattering effects present in grazing-incidence small-angle X-ray scattering (GISAXS) data and interference between them are addressed theoretically as well as experimentally with measurement of a series of patterns at different incident angles, referred to as `incident-angle-resolved GISAXS' (IAR-GISAXS). X-ray reflectivity (XR), GISAXS and IAR-GISAXS of virus particles on Si-substrate supported-polystyrene films have been measured and all the data have been analyzed with appropriate formalisms. It was found that under certain conditions it is possible to extract the correct structural features of the materials from the GISAXS/IAR-GISAXS data using the kinematic SAXS formalisms, without the need to use the …

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Poly[(Nitrato-KO)Tris((Μ3-1h-1,2,4-Triazolato)Dizinc(Ii)]: A Three-Dimensional Coordination Polymer, Josephy M. Ellsworth, Mark D. Smith, Hans-Conrad Zur Loye Oct 2007

Poly[(Nitrato-KO)Tris((Μ3-1h-1,2,4-Triazolato)Dizinc(Ii)]: A Three-Dimensional Coordination Polymer, Josephy M. Ellsworth, Mark D. Smith, Hans-Conrad Zur Loye

Faculty Publications

In the title compound, [Zn2(C2H2N3)3(NO3)], there are two unique Zn atoms, both with site symmetry m. One forms a ZnN3O tetrahedron and the other a ZnN6 octahedron. One and a half 1H-1,2,4-triazolate ligands, with the half-ligand located on a mirror plane, and a disordered nitrate anion complete the asymmetric unit of the structure. The polymeric connectivity is three-dimensional.

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Instrumentation And Metrology For Single Rna Counting In Biological Complexes Or Nanoparticles By A Single-Molecule Dual-View System, Hui Zhang, Dan Shu, Faqing Huang, Peixuan Guo Oct 2007

Instrumentation And Metrology For Single Rna Counting In Biological Complexes Or Nanoparticles By A Single-Molecule Dual-View System, Hui Zhang, Dan Shu, Faqing Huang, Peixuan Guo

Faculty Publications

Limited by the spatial resolution of optical microscopy, direct detection or counting of single components in biological complexes or nanoparticles is challenging, especially for RNA, which is conformationally versatile and structurally flexible. We report here the assembly of a customized single-molecule dual-viewing total internal reflection fluorescence imaging system for direct counting of RNA building blocks. The RNA molecules were labeled with a single fluorophore by in vitro transcription in the presence of a fluorescent AMP. Precise calculation of identical or mixed pRNA building blocks of one, two, three, or six copies within the bacteriophage phi29 DNA packaging motor or other …

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Novel Perturbation Approach For The Structure Factor Of The Attractive Hard-Core Yukawa Fluid, Andrij Trokhymchuk, Roman Melnyk, Filip Moucka, Ivo Nezbeda Sep 2007

Novel Perturbation Approach For The Structure Factor Of The Attractive Hard-Core Yukawa Fluid, Andrij Trokhymchuk, Roman Melnyk, Filip Moucka, Ivo Nezbeda

Faculty Publications

A novel perturbation approach for the structure factor S(k) of the Lennard-Jones-type Yukawa fluid with z=1.8 is presented. An approach is based on a new reference system, that is, the short-range Yukawa model with z0 > z=1.8. By choosing for the reference system the value z0=6, it is shown that (i) the proposed approach for S(k) performs much better than the traditional hard-sphere reference perturbation method does; (ii) the use of an approximate mean spherical (MSA) description of the reference structure factor provides the results for S(k) that are more accurate as those obtained from the direct MSA computations; and (iii) …

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Inclusion Of Electrochemically Active Guests By Novel Oxacalixarene Hosts, Daniel Sobransingh, Mahender B. Dewal, Jacob Hiller, Mark D. Smith, Linda S. Shimizu Sep 2007

Inclusion Of Electrochemically Active Guests By Novel Oxacalixarene Hosts, Daniel Sobransingh, Mahender B. Dewal, Jacob Hiller, Mark D. Smith, Linda S. Shimizu

Faculty Publications

We demonstrate for the first time the utility of oxacalixarenes as hosts and investigate the forces that influence the thermodynamics of binding.

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Snell's Law Of Refraction Observed In Thermal Frontal Polymerization, John A. Pojman, Veronika Viner, Burcu Binici, Shanna Lavergne, Melanie Winsper, Dmitry Golovaty, Laura Gross Sep 2007

Snell's Law Of Refraction Observed In Thermal Frontal Polymerization, John A. Pojman, Veronika Viner, Burcu Binici, Shanna Lavergne, Melanie Winsper, Dmitry Golovaty, Laura Gross

Faculty Publications

We demonstrate that Snell’s law of refraction can be applied to thermal fronts propagating through a boundary between regions that support distinct frontal velocities. We use the free-radical frontal polymerization of a triacrylate with clay filler that allows for two domains containing two different concentrations of a peroxide initiator to be molded together. Because the polymerization reaction rates depend on the initiator concentration, the propagation speed is different in each domain. We study fronts propagating in two parallel strips in which the incident angle is 90°. Our data fit Snell’s law vr/vi = sin θr/sin …

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Synthesis, Characterization, And Cyclopolymerization Of A Functional Non-Symmetric Divinyl Monomer, Bekir Dizman, Lon J. Mathias Aug 2007

Synthesis, Characterization, And Cyclopolymerization Of A Functional Non-Symmetric Divinyl Monomer, Bekir Dizman, Lon J. Mathias

Faculty Publications

A non-symmetric divinyl monomer with terminal carboxylic acid functionality was readily synthesized from the reaction of ethyl α-hydroxymethylacrylate (EHMA) with maleic anhydride. The new monomer (EHMA–MA) was homopolymerized in both bulk and ethyl acetate using AIBN as an initiator to give cyclopolymers. The synthesis of the monomer and cyclopolymers were followed by 13C NMR, 1H NMR, and FTIR. 1H NMR was also utilized to obtain the degree of cyclization of the polymers, which were found to be 95% or higher in all cases. The molecular weights of the cyclopolymers were around 40–60,000 g/mol as estimated by SEC. …

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Poly[Μ2-Nitrato-(Μ4-Pyrazine-2-Carboxylato)Disilver(I)], Kathryn L. Seward, Joseph M. Ellsworth, Zeeshan M. Khaliq, Hans-Conrad Zur Loye Aug 2007

Poly[Μ2-Nitrato-(Μ4-Pyrazine-2-Carboxylato)Disilver(I)], Kathryn L. Seward, Joseph M. Ellsworth, Zeeshan M. Khaliq, Hans-Conrad Zur Loye

Faculty Publications

The title compound, [Ag2(C5H3N2O2)(NO3)]n, is a three-dimensional coordination polymer containing two-dimensional slabs held together by bridging nitrate groups. AgNO4 and AgNO5 silver coordination polyhedra arise. Weak argentophilic interactions [AgAg = 3.0686 (7) Å] occur in the crystal structure.

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Structural Analysis Of Csos1a And The Protein Shell Of The Halothiobacillus Neapolitanus Carboxysome, Yingssu Tsai, Michael R. Sawaya, Gordon C. Cannon, Fei Cai, Eric B. Williams, Sabine Heinhorst, Cheryl A. Kerfeld, Todd O. Yeates Jun 2007

Structural Analysis Of Csos1a And The Protein Shell Of The Halothiobacillus Neapolitanus Carboxysome, Yingssu Tsai, Michael R. Sawaya, Gordon C. Cannon, Fei Cai, Eric B. Williams, Sabine Heinhorst, Cheryl A. Kerfeld, Todd O. Yeates

Faculty Publications

The carboxysome is a bacterial organelle that functions to enhance the efficiency of CO2 fixation by encapsulating the enzymes ribulose bisphosphate carboxylase/ oxygenase (RuBisCO) and carbonic anhydrase. The outer shell of the carboxysome is reminiscent of a viral capsid, being constructed from many copies of a few small proteins. Here we describe the structure of the shell protein CsoS1A from the chemoautotrophic bacterium Halothiobacillus neapolitanus. The CsoS1A protein forms hexameric units that pack tightly together to form a molecular layer, which is perforated by narrow pores. Sulfate ions, soaked into crystals of CsoS1A, are observed in the pores of the …

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Computation Of Correlation Functions And Wave Function Projections In The Context Of Quantum Trajectory Dynamics, Sophya Garashchuk Apr 2007

Computation Of Correlation Functions And Wave Function Projections In The Context Of Quantum Trajectory Dynamics, Sophya Garashchuk

Faculty Publications

The de Broglie-Bohm formulation of the Schrödinger equation implies conservation of the wave function probability density associated with each quantum trajectory in closed systems. This conservation property greatly simplifies numerical implementations of the quantum trajectory dynamics and increases its accuracy. The reconstruction of a wave function, however, becomes expensive or inaccurate as it requires fitting or interpolation procedures. In this paper we present a method of computing wave packet correlation functions and wave function projections, which typically contain all the desired information about dynamics, without the full knowledge of the wave function by making quadratic expansions of the wave function …

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Accumulation Of Pathological Tau Species And Memory Loss In A Conditional Model Of Tauopathy, Zdenek Berger, Hanno Roder, Amanda Hanna, Vijayaraghavan Rangachari, Mei Yue, Zbigniew Wszolek, Karen Ashe, Joshua Knight, Dennis Dickson, Cathy Andorfer, Terrone L. Rosenberry, Jada Lewis, Mike Hutton, Christopher Janus Apr 2007

Accumulation Of Pathological Tau Species And Memory Loss In A Conditional Model Of Tauopathy, Zdenek Berger, Hanno Roder, Amanda Hanna, Vijayaraghavan Rangachari, Mei Yue, Zbigniew Wszolek, Karen Ashe, Joshua Knight, Dennis Dickson, Cathy Andorfer, Terrone L. Rosenberry, Jada Lewis, Mike Hutton, Christopher Janus

Faculty Publications

Neurofibrillary tangles (NFTs) are a pathological hallmark of Alzheimer's disease and other tauopathies, but recent studies in a conditional mouse model of tauopathy (rTg4510) have suggested that NFT formation can be dissociated from memory loss and neurodegeneration. This suggests that NFTs are not the major neurotoxic tau species, at least during the early stages of pathogenesis. To identify other neurotoxic tau protein species, we performed biochemical analyses on brain tissues from the rTg4510 mouse model and then correlated the levels of these tau proteins with memory loss. We describe the identification and characterization of two forms of tau multimers (140 …

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The Niemann-Pick Type C2 Protein Loads Isoglobotrihexosylceramide Onto Cd1d Molecules And Contributes To The Thymic Selection Of Nkt Cells, Paul B. Savage, Nicolas Schrantz, Yuval Sagiv, Yang Liu, Albert Bendelac, Luc Teyton Mar 2007

The Niemann-Pick Type C2 Protein Loads Isoglobotrihexosylceramide Onto Cd1d Molecules And Contributes To The Thymic Selection Of Nkt Cells, Paul B. Savage, Nicolas Schrantz, Yuval Sagiv, Yang Liu, Albert Bendelac, Luc Teyton

Faculty Publications

The Niemann-Pick type C2 (NPC2) protein is a small, soluble, lysosomal protein important for cholesterol and sphingolipid transport in the lysosome. The immunological phenotype of NPC2-deficient mice was limited to an impaired thymic selection of Valpha 14 natural killer T cells (NKT cells) and a subsequent reduction of NKT cells in the periphery. The remaining NKT cells failed to produce measurable quantities of interferon-gamma in vivo and in vitro after activation with alpha-galactosylceramide. In addition, thymocytes and splenocytes from NPC2-deficient mice were poor presenters of endogenous and exogenous lipids to CD1d-restricted Valpha 14 hybridoma cells. Importantly, we determined that similar …

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Precision In Imaging Multivariate Optical Computing, Michael N. Simcock, Michael L. Myrick Mar 2007

Precision In Imaging Multivariate Optical Computing, Michael N. Simcock, Michael L. Myrick

Faculty Publications

Multivariate optical computing (MOC) is a method of performing chemical analysis using a multilayer thin-film structure known as a multivariate optical element (MOE). Recently we have been advancing MOC for imaging problems by using an imaging MOE (IMOE) in a normal-incidence geometry and employing normalization by the 1-norm. There are several important differences between the previously described 45° and the normal-incidence imaging, one of which is the measurement precision due to photon counting. We compare this precision to 45° MOC. We also discuss how MOE models with similar values of standard errors of calibration and prediction and similar gain values …

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Trisodium Dicalcium Bismuth Hexaoxide, Irina V. Puzdrjakova, Rene B. Macquart, Mark D. Smith, Hans-Conrad Zur Loye Feb 2007

Trisodium Dicalcium Bismuth Hexaoxide, Irina V. Puzdrjakova, Rene B. Macquart, Mark D. Smith, Hans-Conrad Zur Loye

Faculty Publications

Single crystals of the title compound, Na3Ca2BiO6, were grown from a high-temperature reactive flux solution of Na2CO3. Na3Ca2BiO6 crystallizes as an ordered rock-salt structure (space group Fddd), in which the octahedral holes in the oxide array are filled by an ordered 3:2:1 arrangement of Na+, Ca2+ and Bi5+ cations. All atoms except for one O atom lie on special positions; site symmetries are as follows: Bi 222, Ca 2, Na 222 and 2, O 2.

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Poly[Diaqua(Μ4-3-Fluorophthalato-Κ4O:O:O':O'')Cadmium(Ii)], Diana Rishmawi, Katie Lewis, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Feb 2007

Poly[Diaqua(Μ4-3-Fluorophthalato-Κ4O:O:O':O'')Cadmium(Ii)], Diana Rishmawi, Katie Lewis, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

The crystal structure of the title compound, [Cd(C8H3FO4)(H2O)2]n, consists of polymeric sheets formed by the bridging of octahedrally coordinated CdII by carboxylate O atoms of the 3-fluorophthalate (3-fpt2-) ligand. The layers exhibit hydrogen bonding between each of two coordinated water molecules and two O atoms of the ligand. Adjacent sheets are connected through - interactions.

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Catena-Poly[[Bis(Α-Thenoyltrifluoroacetonato-Κ2O,O')Copper(Ii)]-Μ-1,4-Di-3-Pyridyl-2,3-Diaza-1,3-Butadiene-Κ2N:N'], William J. Perkins, Tamar Maxwell, Ken B. Williams, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Jan 2007

Catena-Poly[[Bis(Α-Thenoyltrifluoroacetonato-Κ2O,O')Copper(Ii)]-Μ-1,4-Di-3-Pyridyl-2,3-Diaza-1,3-Butadiene-Κ2N:N'], William J. Perkins, Tamar Maxwell, Ken B. Williams, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

The title compound, [Cu(C8H4F3O2S)2(C12H10N4)]n or [Cu(tta)2(L2)2]n (L2 = 1,4-di-3-pyridyl-2,3-diaza-1,3-butadiene and tta = -thenoyltrifluoroacetonate), consists of undulating chains containing two crystallographically distinct CuII centers that are each located on inversion centers. Each CuII center exhibits distorted octahedral coordination provided by two pyridyl N atoms from two equivalent L2 ligands and four O atoms from two equivalent tta ligands. The chains interact through weak C-FH-C contacts.

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Catena-Poly[[Diaquadinitratozinc(Ii)]Bis(Μ-1,4-Di-3-Pyridyl-2,3-Diaza-1,3-Butadiene)], Shakoya Paulin, Pierre Kelly, Kenneth B. Williams, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Jan 2007

Catena-Poly[[Diaquadinitratozinc(Ii)]Bis(Μ-1,4-Di-3-Pyridyl-2,3-Diaza-1,3-Butadiene)], Shakoya Paulin, Pierre Kelly, Kenneth B. Williams, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

The polymeric title complex, [Zn(NO3)2(C24H20N8)(H2O)2]n, features distorted ZnN2O4 octahedra with each ZnII atom being located on an inversion center. Adjacent Zn ions are doubly bridged by two equivalent 1,4-di-3-pyridyl-2,3-diaza-1,3-butadiene ligands to form linear chains.

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Antibacterial Fluoromicas: A Novel Delivery Medium, Bekir Dizman, Jonathan C. Badger, Mohamed O. Elasri, Lon J. Mathias Jan 2007

Antibacterial Fluoromicas: A Novel Delivery Medium, Bekir Dizman, Jonathan C. Badger, Mohamed O. Elasri, Lon J. Mathias

Faculty Publications

Antibacterial fluoromicas were prepared by ion-exchanging fluoromicas with different antibacterial agents including various quaternary ammonium compounds, AgNO3, and norfloxacin. Antibacterial activities of the ion-exchanged fluoromicas were determined against Staphylococcus aureus and Escherichia coli. Minimum inhibitory concentration (MIC) and zone of inhibition (ZOI) tests were performed to determine both antibacterial effectiveness and mode of action associated with the fluoromicas. All treated fluoromicas showed excellent antibacterial activities against both types of bacteria. The antibacterial activities of treated fluoromicas were found to be either better than or the same as those of neat antibacterial agents. The repeated antibacterial activity tests demonstrated …

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