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Articles 139771 - 139800 of 303230

Full-Text Articles in Physical Sciences and Mathematics

Information Diffusion, Facebook Clusters, And The Simplicial Model Of Social Aggregation: A Computational Simulation Of Simplicial Diffusers For Community Health Interventions, Kerk Kee, Lisa Sparks, Daniele C. Struppa, Mirco A. Manucci, Alberto Damiano Sep 2015

Information Diffusion, Facebook Clusters, And The Simplicial Model Of Social Aggregation: A Computational Simulation Of Simplicial Diffusers For Community Health Interventions, Kerk Kee, Lisa Sparks, Daniele C. Struppa, Mirco A. Manucci, Alberto Damiano

Communication Faculty Articles and Research

By integrating the simplicial model of social aggregation with existing research on opinion leadership and diffusion networks, this article introduces the constructs of simplicial diffusers (mathematically defined as nodes embedded in simplexes; a simplex is a socially bonded cluster) and simplicial diffusing sets (mathematically defined as minimal covers of a simplicial complex; a simplicial complex is a social aggregation in which socially bonded clusters are embedded) to propose a strategic approach for information diffusion of cancer screenings as a health intervention on Facebook for community cancer prevention and control. This approach is novel in its incorporation of interpersonally bonded clusters, …

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Forecasting Climate Change Impacts On The Distribution Of Wetland Habitat In The Midwestern United States, Heath Garris, Randall Mitchell, Lauchlan Fraser, Linda Barrett Sep 2015

Forecasting Climate Change Impacts On The Distribution Of Wetland Habitat In The Midwestern United States, Heath Garris, Randall Mitchell, Lauchlan Fraser, Linda Barrett

Linda R. Barrett

Shifting precipitation patterns brought on by climate change threaten to alter the future distribution of wetlands. We developed a set of models to understand the role climate plays in determining wetland formation on a landscape scale and to forecast changes in wetland distribution for the Midwestern United States. These models combined 35 climate variables with 21 geographic and anthropogenic factors thought to encapsulate other major drivers of wetland distribution for the Midwest. All models successfully recreated a majority of the variation in current wetland area within the Midwest, and showed that wetland area was significantly associated with climate, even when …

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Controls On Trace Metal Authigenic Enrichment In Reducing Sediments: Insights From Modern Oxygen-Deficient Settings, Susan Little, Derek Vance, Timothy Lyons, James Mcmanus Sep 2015

Controls On Trace Metal Authigenic Enrichment In Reducing Sediments: Insights From Modern Oxygen-Deficient Settings, Susan Little, Derek Vance, Timothy Lyons, James Mcmanus

James McManus

Any effort to reconstruct Earth history using variations in authigenic enrichments of redox-sensitive and biogeochemically important trace metals must rest on a fundamental understanding of their modern oceanic and sedimentary geochemistry. Further, unravelling the multiple controls on sedimentary enrichments requires a multi-element approach. Of the range of metals studied, most is known about the behavior of Fe, Mn, and Mo. In this study, we compare the authigenic enrichment patterns of these elements with a group whose behavior is not as well defined (Cd, Cu, Zn, and Ni) in three oxygen-poor settings: the Black Sea, the Cariaco Basin (Venezuela), and the …

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The Sedimentary Flux Of Dissolved Rare Earth Elements To The Ocean, April Abbott, Brian Haley, James Mcmanus, Clare Reimers Sep 2015

The Sedimentary Flux Of Dissolved Rare Earth Elements To The Ocean, April Abbott, Brian Haley, James Mcmanus, Clare Reimers

James McManus

We determined pore fluid rare earth element (REE) concentrations in near-surface sediments retrieved from the continental margin off Oregon and California (USA). These sites represent shelf-to-slope settings, which lie above, within, and below the oxygen minimum zone of the Northeast Pacific. The sediments are characterized by varying degrees of net iron reduction, with pore fluids from the shelf sites being generally ferruginous, and the slope sediments having less-pronounced iron reduction zones that originate deeper in the sediment package. REE concentrations show maxima in shallow (upper 2–10 cm) subsurface pore fluids across all sites with concentrations that rise more than two …

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On The Isotope Composition Of Reactive Iron In Marine Sediments: Redox Shuttle Versus Early Diagenesis, Florian Shultz, Silke Severman, James Mcmanus, Anna Nofke, Ulrike Lomnitz, Christian Hensen Sep 2015

On The Isotope Composition Of Reactive Iron In Marine Sediments: Redox Shuttle Versus Early Diagenesis, Florian Shultz, Silke Severman, James Mcmanus, Anna Nofke, Ulrike Lomnitz, Christian Hensen

James McManus

The isotope composition of reactive iron (Fe) in marine sediments and sedimentary rocks is a promising tool for identifying Fe sources and sinks across ocean basins. In addition to cross-basinal Fe redistribution, which can modify Fe isotope signatures, Fe minerals also undergo diagenetic redistribution during burial. The isotope fractionation associated with this redistribution does not affect the bulk isotope composition, but complicates the identification of mineral- specific isotope signatures. Here, we present new Fe isotope data for Peru margin sediments and revisit previously published data for sediments from the California margin to unravel the impact of early diagenesis on Fe …

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Computing Invariant Dynamics For Differential Equations: Spectral Methods, Errors, And Computer Assisted Proof, J. D. Mireles James Sep 2015

Computing Invariant Dynamics For Differential Equations: Spectral Methods, Errors, And Computer Assisted Proof, J. D. Mireles James

Mathematics Colloquium Series

The qualitative theory of dynamical systems is concerned with studying the long time behavior discrete and continuous time models such as nonlinear differential equations. The long time behavior of such models is organized by landmarks called invariant sets. For complicated nonlinear equations these invariant sets are difficult to study via pen and paper analysis, and we typically employ numerical simulations to gain insights into the dynamics. If we now think of these computer assisted insights as mathematical conjectures, then it is natural to ask how we might obtain proofs. Since the conjectures themselves originate with the computer it is not …

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Transitions Of Tethered Chain Molecules Under Tension, Jutta Luettmer-Strathmann, Kurt Binder Sep 2015

Transitions Of Tethered Chain Molecules Under Tension, Jutta Luettmer-Strathmann, Kurt Binder

Jutta Luettmer-Strathmann

An applied tension force changes the equilibrium conformations of a polymer chain tethered to a planar substrate and thus affects the adsorption transition as well as the coil-globule and crystallization transitions. Conversely, solvent quality and surface attraction are reflected in equilibrium force-extension curves that can be measured in experiments. To investigate these effects theoretically, we study tethered chains under tension with Wang-Landau simulations of a bond-fluctuation lattice model. Applying our model to pulling experiments on biological molecules we obtain a good description of experimental data in the intermediate force range, where universal features dominate and finite size effects are small. …

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Partition Function Zeros And Finite Size Scaling For Polymer Adsorption, Mark Taylor, Jutta Luettmer-Strathmann Sep 2015

Partition Function Zeros And Finite Size Scaling For Polymer Adsorption, Mark Taylor, Jutta Luettmer-Strathmann

Jutta Luettmer-Strathmann

The zeros of the canonical partition functions for a flexible polymer chain tethered to an attractive flat surface are computed for chains up to length N = 1536. We use a bond-fluctuation model for the polymer and obtain the density of states for the tethered chain by Wang-Landau sampling. The partition function zeros in the complex e(β)-plane are symmetric about the real axis and densest in a boundary region that has the shape of a nearly closed circle, centered at the origin, terminated by two flaring tails. This structure defines a root-free zone about the positive real axis and follows …

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A New Microenvironment For The Formation Of Clay Minerals: The Example Of Authigenic Halloysite-7Å And Gibbsite In A Stalactite From Agios Georgios Cave, Kilkis, North Greece, Elena Ifandi, Basilios Tsikouras, Dimitrios Papoulis, Konstantin Hatzipanagiotou, Aspasia Antonelou Sep 2015

A New Microenvironment For The Formation Of Clay Minerals: The Example Of Authigenic Halloysite-7Å And Gibbsite In A Stalactite From Agios Georgios Cave, Kilkis, North Greece, Elena Ifandi, Basilios Tsikouras, Dimitrios Papoulis, Konstantin Hatzipanagiotou, Aspasia Antonelou

International Journal of Speleology

An unusual authigenic origin for halloysite and gibbsite is reported in a stalactite from Agios Georgios Cave, Kilkis. This speleothem includes mostly pure calcite whereas minor areas of Mg-rich calcite and scarce dolomite are present in four growth phases. Abundant pores are created due to imperfect coalescence of the calcite crystals. Several of them contain detrital muscovite, which was presumably transferred from the dripping water, during the formation of speleothem and has been variably altered to halloysite. Several pores in the stalactite contain different mineral assemblages that we interpret as in situ: halloysite-7Å, halloysite + silica, gibbsite + silica and …

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Speleogenesis Of The Hermannshöhle Cave System (Austria): Constraints From 230Th/U-Dating And Palaeomagnetic Analysis, Lukas Plan, Andrea Schober, Denis Scholz, Christoph Spötl, Petr Pruner, Pavel Bosák Sep 2015

Speleogenesis Of The Hermannshöhle Cave System (Austria): Constraints From 230Th/U-Dating And Palaeomagnetic Analysis, Lukas Plan, Andrea Schober, Denis Scholz, Christoph Spötl, Petr Pruner, Pavel Bosák

International Journal of Speleology

Hermannshöhle is a show cave located near Kirchberg/Wechsel in Lower Austria. Together with three nearby and genetically connected caves, it forms the Hermannshöhlen cave system (HHS). With a length of 5 km, the HHS is the longest cave in the Lower Austroalpine unit. It is arranged as an extreme three-dimensional maze on a ground area of 200 x 200 x 82 m. Speleothems are abundant in this cave and represent the focus of this study. Low carbon isotope values indicate the presence of a soil-covered catchment above the HHS during times of speleothem deposition. 28 samples were dated by the …

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The Firece Green Fire: Vol. 6 Issue 1, Wofford College Environmental Studies Program Sep 2015

The Firece Green Fire: Vol. 6 Issue 1, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

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Utilization Of Antibody-Conjugated Gold Nanoparticles, Dynamic Light Scattering And Sers In Influenza Virus Detection, Yen Hoang Lai Sep 2015

Utilization Of Antibody-Conjugated Gold Nanoparticles, Dynamic Light Scattering And Sers In Influenza Virus Detection, Yen Hoang Lai

Theses and Dissertations

Influenza A H3N2, H1N1, and influenza B viruses primarily cause winter illness in humans, leading to significant morbidity and mortality in the population of the very young, the elderly, and people with chronic disease. In addition to the regular seasonal epidemics of influenza, influenza pandemics associated with the emergence of new influenza A strains are threatening due to high levels of mortality, social disruption, and economic losses. These novel strains are not affected by the human immunity developed to older strains of influenza, therefore can spread readily and infect a vast number of people. The most recent flu pandemic outbreak …

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Bulk Equations Of Motion From Cft Correlators, Daniel N. Kabat, Gilad Lifschytz Sep 2015

Bulk Equations Of Motion From Cft Correlators, Daniel N. Kabat, Gilad Lifschytz

Publications and Research

ToO (1/N) we derive, purely from CFT data, the bulk equations of motion for interacting scalar fields and for scalars coupled to gauge fields and gravity. We first uplift CFT operators to mimic local AdS fields by imposing bulk microcausality. This requires adding an infinite tower of smeared higher-dimension double-trace operators to the CFT definition of a bulk field, with coefficients that we explicitly compute. By summing the contribution of the higher-dimension operators we derive the equations of motion satisfied by these uplifted CFT operators and show that we precisely recover the expected bulk equations of motion. We exhibit the …

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More Coastal Nuisance Flooding Forecast For Coming Months, Associated Press Sep 2015

More Coastal Nuisance Flooding Forecast For Coming Months, Associated Press

News Items

No abstract provided.

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Synthesis, Crystal Structures, And Dft Calculations Of Three New Cyano(Phenylsulfonyl)Indoles And A Key Synthetic Precursor Compound, William Montgomery, Justin Lopchuk, Gordon Gribble, Jerry Jasinski Sep 2015

Synthesis, Crystal Structures, And Dft Calculations Of Three New Cyano(Phenylsulfonyl)Indoles And A Key Synthetic Precursor Compound, William Montgomery, Justin Lopchuk, Gordon Gribble, Jerry Jasinski

Dartmouth Scholarship

Three cyano-1-(phenylsulfonyl)indole derivatives, 3-cyano-1-(phenylsulfonyl) indole, (I), 2-cyano-1-(phenylsulfonyl)indole, (II), and 2,3-dicyano-1-(phenylsulfonyl) indole, (III), and a key synthetic precursor 1-(phenylsulfonyl)-1-(1,1-dimethylethyl) indole-3-carboxamide, (IV), have been synthesized and their structures determined by single crystal X-ray crystallography. (I), C15H10N2O2S, is orthorhombic with space group P 212121 and cell constants: a = 4.9459(3) Å, b = 10.5401(7) Å, c = 25.0813(14) Å, V = 1307.50(14) Å3 and Z = 4. (II), C15H10N2O2S, …

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Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee Berger, John Hawks, Darryl J. De Ruiter, Steve E. Churchill, Peter Schmid, Lucas Delezene, Tracy Kivell, Heather Garvin, Scott Williams, Jeremy Desilva Sep 2015

Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee Berger, John Hawks, Darryl J. De Ruiter, Steve E. Churchill, Peter Schmid, Lucas Delezene, Tracy Kivell, Heather Garvin, Scott Williams, Jeremy Desilva

Dartmouth Scholarship

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot and lower …

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Nanograv Constraints On Gravitational Wave Bursts With Memory, Z. Arzoumanian, A. Brazier, S. Burke-Spolaor, S. J. Chamberlin, S. Chatterjee, B. Christy, J. M. Cordes, N. J. Cornish, Fredrick A. Jenet, Jing Luo Sep 2015

Nanograv Constraints On Gravitational Wave Bursts With Memory, Z. Arzoumanian, A. Brazier, S. Burke-Spolaor, S. J. Chamberlin, S. Chatterjee, B. Christy, J. M. Cordes, N. J. Cornish, Fredrick A. Jenet, Jing Luo

Physics and Astronomy Faculty Publications and Presentations

Among efforts to detect gravitational radiation, pulsar timing arrays are uniquely poised to detect \"memory\" signatures, permanent perturbations in spacetime from highly energetic astrophysical events such as mergers of supermassive black hole binaries. The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) observes dozens of the most stable millisecond pulsars using the Arecibo and Green Bank radio telescopes in an effort to study, among other things, gravitational wave memory. We herein present the results of a search for gravitational wave bursts with memory (BWMs) using the first five years of NANOGrav observations. We develop original methods for dramatically speeding up …

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Identifying The Tautomeric Form Of A Deoxyguanosine-Estrogen Quinone Intermediate, Douglas E. Stack Sep 2015

Identifying The Tautomeric Form Of A Deoxyguanosine-Estrogen Quinone Intermediate, Douglas E. Stack

Chemistry Faculty Publications

Mechanistic insights into the reaction of an estrogen o-quinone with deoxyguanosine has been further investigated using high level density functional calculations in addition to the use of 4-hyroxycatecholestrone (4-OHE1) regioselectivity labeled with deuterium at the C1-position. Calculations using the M06-2X functional with large basis sets indicate the tautomeric form of an estrogen-DNA adduct present when glycosidic bonds cleavage occurs is comprised of an aromatic A ring structure. This tautomeric form was further verified by use of deuterium labelling of the catechol precursor use to form the estrogen o-quinone. Regioselective deuterium labelling at the C1-position of the estrogen A ring allows …

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Observations Of An Energetically Isolated Quiet Sun Transient: Evidence Of Quasi-Steady Coronal Heating, Norton Brice Orange, David L. Chesney, Hakeem M. Oluseyi Sep 2015

Observations Of An Energetically Isolated Quiet Sun Transient: Evidence Of Quasi-Steady Coronal Heating, Norton Brice Orange, David L. Chesney, Hakeem M. Oluseyi

Aerospace, Physics, and Space Science Faculty Publications

Increasing evidence for coronal heating contributions from cooler solar atmospheric layers, notably quiet Sun (QS) conditions, challenges standard solar atmospheric descriptions of bright transition region (TR) emission. As such, questions about the role of dynamic QS transients in contributing to the total coronal energy budget are raised. Using observations from the Atmospheric Imaging Assembly and Heliosemic Magnetic Imager on board the Solar Dynamics Observatory, and numerical model extrapolations of coronal magnetic fields, we investigate a dynamic QS transient that is energetically isolated to the TR and extrudes from a common footpoint shared with two heated loop arcades. A non-causal relationship …

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Implementation Techniques For The Truncated Fourier Transform, Li Zhang Sep 2015

Implementation Techniques For The Truncated Fourier Transform, Li Zhang

Electronic Thesis and Dissertation Repository

We study various algorithms for the Truncated Fourier Transform (TFT) which is a variation of the Discrete Fourier Transform (DFT) that allows one to work with an input vector of arbitrary size without zero padding. After a review of the original algorithms for the forward and inverse TFT introduced by J. van der Hoeven, we consider the variation of D. Harvey as well as that of J. Johnson and L.C. Meng. Both variations are based on Cooley-Tukey like formulas. The former is called strict general radix as it strictly follows the specifications proposed by J. van der Hoeven, while the …

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Editorial Of Special Issue: Nanomaterials As Photocatalysts, Mohammad Mansoob Khan Dr Sep 2015

Editorial Of Special Issue: Nanomaterials As Photocatalysts, Mohammad Mansoob Khan Dr

Dr. Mohammad Mansoob Khan

This thematic special issue entitled “Nanomaterials as Photocatalysts” based on selected research/review articles submitted to the Journal of Saudi Chemical Society focuses on the visible/UV light photocatalytic activities of the selected nanomaterials. Topics of these research/review articles cover diverse and exciting areas of research related to nanomaterials such as metal oxides, nanoparticles, nanocomposites, their synthesis, and photocatalysis for waste water treatment, photocatalysis for effective conversion of waste, photochemical conversions, energy generation and other chemical energy production.

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Fate Of Quasiparticles In The Superconducting State, Sasa Dordevic, D. Van Der Marel, C. C. Homes Sep 2015

Fate Of Quasiparticles In The Superconducting State, Sasa Dordevic, D. Van Der Marel, C. C. Homes

Sasa V. Dordevic

Quasiparticle properties in the superconducting state are masked by the superfluid and are not directly accessible to infrared spectroscopy. We show how one can use a Kramers-Kronig transformation to separate the quasiparticle from superfluid response and extract intrinsic quasiparticle properties in the superconducting state. We also address the issue of a narrow quasiparticle peak observed in microwave measurements, and demonstrate how it can be combined with infrared measurements to obtain a unified picture of electrodynamic properties of cuprate superconductors.

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Dielectric Behavior Of 95.5% Pb(Zn1/3nb2/3)O-3-4.5% Pbtio3 Single Crystals Under Dc Bias From 12-550 K, Ang Chen, Zhi Yu Sep 2015

Dielectric Behavior Of 95.5% Pb(Zn1/3nb2/3)O-3-4.5% Pbtio3 Single Crystals Under Dc Bias From 12-550 K, Ang Chen, Zhi Yu

Ang Chen

This work reports a detailed study of the dielectric behavior of 95.5% Pb(Zn1/3Nb2/3)O-3 - 4.5% PbTiO3 (PZN-4.5PT) single crystals with and without dc bias. It is found that there are at least five sets of dielectric anomalies for PZN-4.5PT from 12K to 550K. There are two dielectric peaks, around 430K and 395K, which are referred to as cubic-tetragonal and tetragonal- rhombohedral phase transitions, respectively, above room temperature. Furthermore, a set of broad peaks around 350K (at 10kHz) that showed up under electric field of 10kV/cm might indicate the existence of a monoclinic distortion M-A phase.

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Adhesion And Friction Characteristics Of Carbon Nanotube Arrays, Alper Buldum Sep 2015

Adhesion And Friction Characteristics Of Carbon Nanotube Arrays, Alper Buldum

Alper Buldum

There has been a great deal of interest in understanding, design and fabrication of bio-mimetic and bio-inspired adhesives in recent years. In this paper we present theoretical investigations on adhesion, friction behaviors and characteristics of fibrillar arrays composed of noninteracting carbon nanotubes for bio-inspired dry adhesives. Contact, compression, subsequent pulling off and dry sliding friction simulations were performed. It is demonstrated that there are two different adhesion forces during pull off. Static friction force values are in between 40 and 60 N cm(-2) at different loads and they are significantly larger than the normal adhesion forces. Dynamic friction force and …

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Pentacene-Fused Diporphyrins, Lin Jiang, James Engle, Ross Zaenglein, Alex Matus, Christopher Ziegler, Hong Wang, Martin Stillman Sep 2015

Pentacene-Fused Diporphyrins, Lin Jiang, James Engle, Ross Zaenglein, Alex Matus, Christopher Ziegler, Hong Wang, Martin Stillman

Christopher J. Ziegler

In this work, we report the synthesis, spectroscopic characterization, and theoretical analysis of a linearly conjugated pentacene-fused porphyrin dimer and cross-conjugated quinone-fused dinaphtho[2,3]porphyrins. These multichromophoric systems display non-typical UV-visible absorptions of either porphyrins or pentacenes/quinones. UV-visible, emission and magnetic circular dichroism (MCD) spectroscopy suggest strong electronic interactions among the multichromophores in the system. DFT calculations revealed the delocalization of the HOMOs and LUMOs spanning the entire dimer and linker assembly. The pentacene-fused porphyrin dimer is significantly more stable than both the corresponding pentacene and the heptacene derivatives. The availability of these huge π-extended and electronically highly interactive multichromophoric systems promises …

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Combined Mcd/Dft/Tddft Study Of The Electronic Structure Of Axially Pyridine Coordinated Metallocorroles, Hannah Rhoda, Laura Crandall, G. Geier, Christopher Ziegler, Victor Nemykin Sep 2015

Combined Mcd/Dft/Tddft Study Of The Electronic Structure Of Axially Pyridine Coordinated Metallocorroles, Hannah Rhoda, Laura Crandall, G. Geier, Christopher Ziegler, Victor Nemykin

Christopher J. Ziegler

A series of metallocorroles were investigated by UV−vis and MCD spectroscopies to investigate similarities and differences in the electronic structure and spectroscopy of the closed- and open-shell metallocorroles. Similar to the free-base H3tpfc, inspection of the MCD Faraday B-terms for all of the macrocycles presented here revealed that a ΔHOMO < ΔLUMO condition is present for each complex, which results in an unusual sign-reversed sequence for π−π* transitions in their MCD spectra.

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Synthesis Of Dimeric Rhenium Phenylenediimine Conjugates, Christopher Ziegler, J Bass, C Bogdanowicz, R Herrick, A Hasheminasab Sep 2015

Synthesis Of Dimeric Rhenium Phenylenediimine Conjugates, Christopher Ziegler, J Bass, C Bogdanowicz, R Herrick, A Hasheminasab

Christopher J. Ziegler

No abstract provided.

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Improved Synthesis Of [Re(Co)(3)(H2o)(3)]Br And Its Derivatives, Gerard Kerins, Joshua Farrell, Richard Herrick, Christopher Ziegler Sep 2015

Improved Synthesis Of [Re(Co)(3)(H2o)(3)]Br And Its Derivatives, Gerard Kerins, Joshua Farrell, Richard Herrick, Christopher Ziegler

Christopher J. Ziegler

Rhenium has been studied at length as a non-radioactive chemical analog to Technetium, a popular diagnostic imaging agent employed in nuclear medicine and biology. This study details a new synthetic method for preparing [Re(CO)3(H2O)3]Br as well as multiple derivatives of this complex using tridentate ligands. Full synthetic details and characterization will be pre

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Enhanced Helical Folding Of Ortho-Phenylenes Through The Control Of Aromatic Stacking Interactions, Sanyo Mathew, Laura Crandall, Christopher Ziegler Sep 2015

Enhanced Helical Folding Of Ortho-Phenylenes Through The Control Of Aromatic Stacking Interactions, Sanyo Mathew, Laura Crandall, Christopher Ziegler

Christopher J. Ziegler

The ortho-phenylenes are a simple class of foldamers, with the formation of helices driven by offset aromatic stacking interactions parallel to the helical axis. For the majority of reported o-phenylene oligomers, the perfectly folded conformer comprises perhaps 50–75% of the total population. Given the hundreds or thousands of possible conformers for even short oligomers, this distribution represents a substantial bias toward the folded state. However, “next-generation” o-phenylenes with better folding properties are needed if these structures are to be exploited as functional units within more complex architectures. Here, we report several new series of o-phenylene oligomers, varying both the nature …

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Structure And Conformation Of The Medium-Sized Chlorophosphazene Rings, Bowers, David Bowers, Brian Wright, Vincenzo Scionti, Anthony Schultz, Matthew Panzner, Eric Twum, Lin-Lin Li, Bryan Katzenmeyer, Benjamin Thome, Peter Rinaldi, Chrys Wesdemiotis, Wiley Youngs, Claire Tessier Sep 2015

Structure And Conformation Of The Medium-Sized Chlorophosphazene Rings, Bowers, David Bowers, Brian Wright, Vincenzo Scionti, Anthony Schultz, Matthew Panzner, Eric Twum, Lin-Lin Li, Bryan Katzenmeyer, Benjamin Thome, Peter Rinaldi, Chrys Wesdemiotis, Wiley Youngs, Claire Tessier

Wiley J. Youngs

No abstract provided.

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