Search Results - "DeGraff, B. A."

Luminescent Transition Metal Complexes as Sensors:  Structural Effects on pH Response by Higgins, Bernadette, DeGraff, B. A, Demas, J. N

“…A series of luminescent transition metal complexes using the pH-sensitive ligand 5-carboxy-1,10-phenanthroline has been synthesized and characterized. The…”
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Luminescence Lifetime Standards for the Nanosecond to Microsecond Range and Oxygen Quenching of Ruthenium(II) Complexes by Morris, Kaleem J, Roach, Michael S, Xu, Wenying, Demas, J. N, DeGraff, B. A

“…A rapid and reproducible method for determining the temperature dependence of luminescence lifetimes has been developed. With the use of this method, a set of…”
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Oxygen sensors based on luminescence quenching by DEMAS, J. N, DEGRAFF, B. A, COLEMAN, P. B

“…As an optical detection strategy, luminescence offers many advantages such as excellent sensitivity and selectivity. James N. Demas of the University of…”
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Modeling of Luminescence Quenching-Based Sensors: Comparison of Multisite and Nonlinear Gas Solubility Models by Demas, J. N, DeGraff, B. A, Xu, Wenying

“…Quenching-based luminescence sensors exhibit nonlinear Stern-Volmer quenching behavior. Two common explanations of the nonlinearity are either multisite…”
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Optimized Gating Scheme for Rapid Lifetime Determinations of Single-Exponential Luminescence Lifetimes by Chan, Sing Po, Fuller, Z. J, Demas, J. N, DeGraff, B. A

“…The rapid lifetime method (RLD) for determining excited-state lifetimes uses the ratio of the areas under two regions of the decay. To get good precision with…”
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Viscosity and Temperature Effects on the Rate of Oxygen Quenching of Tris-(2,2′-bipyridine)ruthenium(II) by Reynolds, Evan W., Demas, J. N., DeGraff, B. A.

“…We compare the bimolecular quenching rate constant (k 2 ) of luminescent tris(2,2′-bipyridine)ruthenium(II) by oxygen in water, ethylene glycol and glycerol as…”
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Photophysical and Analyte Sensing Properties of Cyclometalated Ir(III) Complexes by Leavens, Bethany B. H., Trindle, Carl O., Sabat, Michal, Altun, Zikri, Demas, James N., DeGraff, B. A.

“…The synthesis of some heteroleptic, cyclometalated iridium(III) complexes is described. The utility of these [Ir(ppy) 2 (N-N)]Cl (ppy = 2-phenylpyridine and…”
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Photostability of Luminescent Ruthenium(II) Complexes in Polymers and in Solution by Fuller, Z. J, Bare, W. D, Kneas, K. A, Xu, W.-Y, Demas, J. N, DeGraff, B. A

“…The effects of oxygen on the photochemical properties of ruthenium(II) complexes in solution and in polymers are reported. In solution, the complex is actually…”
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Comparison of Methods for Rapid Evaluation of Lifetimes of Exponential Decays by Moore, Christopher, Chan, Sing Po, Demas, J. N., DeGraff, B. A.

“…For evaluating exponential luminescence decays, there are a variety of computational rapid integral methods based on the areas of the decay under different…”
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Photophysics and photochemistry of oxygen sensors based on luminescent transition-metal complexes by Carraway, E. R, Demas, J. N, DeGraff, B. A, Bacon, J. R

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Oxygen Sensors Based on Luminescence Quenching: Interactions of Metal Complexes with the Polymer Supports by Xu, Wenying, McDonough, Robert Clayton, Langsdorf, Brandi, Demas, J. N, DeGraff, B. A

“…Oxygen quenching of [Ru(Ph2phen)3]Cl2 (Ph2phen = 4,7-diphenyl-1,10-phenanthroline) has been studied in a diverse series of polymers, most with a common…”
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Lifetime-Based pH Sensor System Based on a Polymer-Supported Ruthenium(II) Complex by Clarke, Yvette, Xu, Wenying, Demas, J. N, DeGraff, B. A

“…A new luminescence lifetime-based pH sensor system is described. The system is based on [Ru(Ph2phen)2DCbpy]2+ (DCbpy = 4,4‘-dicarboxy-2,2‘-bipyridine)…”
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Oxygen Sensors Based on Luminescence Quenching of Metal Complexes:  Osmium Complexes Suitable for Laser Diode Excitation by Xu, Wenying, Kneas, Kristi A., Demas, J. N., DeGraff, B. A.

“…Oxygen quenching of a series of Os(II) complexes with α-diimine ligands has been studied in a predominantly poly(dimethylsiloxane) (PDMS) polymer and in Gp-163…”
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Method for Measuring Oxygen Diffusion Coefficients of Polymer Films by Luminescence Quenching by Kneas, Kristi A, Demas, J. N, Nguyen, Bryant, Lockhart, Aaron, Xu, Wenying, DeGraff, B. A

“…To ascertain the relationship between the physical properties of polymer supports and the observed response of luminescence-based oxygen sensors, a…”
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Long-lived, highly luminescent rhenium(I) complexes as molecular probes: intra- and intermolecular excited-state interactions by Sacksteder, LouAnn, Lee, Maria, Demas, J. N, DeGraff, B. A

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Quantum Dots: An Experiment for Physical or Materials Chemistry by Winkler, L. D, Arceo, J. F, Hughes, W. C, DeGraff, B. A, Augustine, B. H

“…An experiment involving the synthesis and optical characterization of nanoparticles of the semiconductor CdS is described. The synthesis uses inexpensive…”
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Applications of Luminescent Transition Metal Complexes to Sensor Technology and Molecular Probes by Demas, J. N, DeGraff, B. A

“…An overview of the applications of luminescent transition metal complexes to sensor technology is presented. In addition to general considerations, a number of…”
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Polymer-Supported pH Sensors Based on Hydrophobically Bound Luminescent Ruthenium(II) Complexes by Price, Jason M, Xu, Wenying, Demas, J. N, DeGraff, B. A

“…A new luminescence intensity-based sensor-polymer support system is described. The pH-sensitive element is [Ru(phen)2[phen(OH)2]]2+ or…”
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Elimination of Fluorescence and Scattering Backgrounds in Luminescence Lifetime Measurements Using Gated-Phase Fluorometry by Rowe, H. M, Chan, Sing Po, Demas, J. N, DeGraff, B. A

“…A new gated form of phase fluorometry for measuring lifetimes is presented. The technique uses a square-wave excitation and gates the detector on only during…”
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Oxygen sensors based on luminescence quenching: interactions of pyrene with the polymer supports by Xu, Wenying, Schmidt, Robert, Whaley, M, Demas, J. N, DeGraff, B. A, Karikari, E. K, Famer, B. A

“…Oxygen quenching of pyrene has been studied in a diverse series of polymers. Most measurements were made using homo- or copolymers containing a…”
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