Cynthia Corley | University of North Carolina at Chapel Hill (original) (raw)
Papers by Cynthia Corley
Journal of Chromatography A, Nov 1, 2005
The chemometric resolution and quantification of overlapped peaks from comprehensive two-dimensio... more The chemometric resolution and quantification of overlapped peaks from comprehensive two-dimensional (2D) liquid chromatography (LC × LC) data are demonstrated. The LC × LC data is produced from an in-house LC × LC analyzer that couples an anion-exchange column via a multi-port valve with a reversed-phase column connected to a UV absorbance detector. Three test mixtures, each containing a target analyte, are subjected to partial LC × LC separations to simulate likely cases of signal overlap. The resulting unresolved target-analyte signals are then analyzed by the standard-addition method and two chemometric methods. The LC × LC analyses of a test mixture and its corresponding standard-addition mixture results in two data matrices, one for each mixture. The stacking of these two data matrices produces a data structure that can then be analyzed by trilinear chemometric methods. One method, the generalized rank annihilation method (GRAM), uses a non-iterative eigenvalue-based approach to mathematically resolve overlapped trilinear signals. The other method, parallel factor analysis (PARAFAC), uses an iterative approach to resolve trilinear signals by the optimization of initial estimates using alternating least squares and signal constraints. In this paper, GRAM followed by PARAFAC analysis is shown to produce better qualitative and quantitative results than using each method separately. For instance, for all three test mixtures, the GRAM-PARAFAC approach improved quantitative accuracy by at least a factor of 4 and quantitative precision by more than 2 when compared to GRAM alone. This paper also introduces a new means of correcting run-to-run retention time shifts in comprehensive 2D chromatographic data.
Acta Crystallographica Section E: Crystallographic Communications, Jul 4, 2019
Five new crystal structures of perfluoropyridine substituted in the 4-position with phenoxy, 4-br... more Five new crystal structures of perfluoropyridine substituted in the 4-position with phenoxy, 4-bromophenoxy, naphthalen-2-yloxy, 6-bromonaphthalen-2yloxy, and 4,4 0-biphenoxy are reported, viz. 2,3,5,6-tetrafluoro-4-phenoxypyridine, C 11 H 5 F 4 NO (I), 4-(4-bromophenoxy)-2,3,5,6-tetrafluoropyridine, C 11 H 4 BrF 4 NO (II), 2,3,5,6-tetrafluoro-4-[(naphthalen-2-yl)oxy]pyridine, C 15 H 7 F 4 NO (III), 4-[(6-bromonaphthalen-2-yl)oxy]-2,3,5,6-tetrafluoropyridine, C 15 H 6 BrF 4 NO (IV), and 2,2 0-bis[(perfluoropyridin-4-yl)oxy]-1,1 0-biphenyl, C 22 H 8 F 8 N 2 O 2 (V). The dihedral angles between the aromatic ring systems in I-IV are 78.74 (8), 56.35 (8), 74.30 (7), and 64.34 (19) , respectively. The complete molecule of V is generated by a crystallographic twofold axis: the dihedral angle between the pyridine ring and adjacent phenyl ring is 80.89 (5) and the equivalent angle between the biphenyl rings is 27.30 (5). In each crystal, the packing is driven by C-HÁ Á ÁF interactions, along with a variety of C-FÁ Á Á, C-HÁ Á Á, C-BrÁ Á ÁN, C-HÁ Á ÁN, and C-BrÁ Á Á contacts. Hirshfeld surface analysis was conducted to aid in the visualization of these various influences on the packing. research communications
ECS Meeting Abstracts, 2006
not Available.
Kluwer Academic Publishers eBooks, Dec 2, 2005
Industrial & Engineering Chemistry Research, Apr 15, 2008
Industrial & Engineering Chemistry Research, May 26, 2009
Ionic liquids have the potential for being ideal alternatives for organic solvents in chemical wa... more Ionic liquids have the potential for being ideal alternatives for organic solvents in chemical warfare agent reactions and demilitarization processes. They are considered to be an excellent substitute, because of their extraordinarily wide liquid range, low melting points, chemical ...
University of Colorado Colorado Springs. Kraemer Family Library, May 1, 2018
Journal of Fluorine Chemistry, 2020
Macromolecular Chemistry and Physics, 2020
Two new trifunctional alkene monomers based on the highly modular perfluoropyridine scaffold are ... more Two new trifunctional alkene monomers based on the highly modular perfluoropyridine scaffold are synthesized with an aliphatic and an aromatic moiety, 4‐penten‐1‐ol and eugenol, respectively. The monomers are the basis for thiol‐ene thermoset materials, formulated against a difunctional or trifunctional thiol. Systems based on these novel monomers have a wide range of thermal properties, with glass transition temperatures (Tgs) spanning from −42 to 21 °C. Mixed systems obey the Fox equation, and Tgs of the mixtures can be tuned to specific values in that range. Thermal degradation temperatures follow a similar trend, with decomposition temperatures ranging from 274 to 348 °C in nitrogen with varying compositions having tailorability therein. This new class of semifluorinated thermoset materials with tunable thermal properties has several potential applications within the aerospace industry, such as sealants and coatings, where stability and survivability at high temperatures in hars...
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this
Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is est... more Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 12 December 2015 2. RE...
Journal of Fluorine Chemistry, 2019
The Journal of Physical Chemistry A, 2019
Separations, 2019
There are many advantages to using ionic liquids as solvents or catalysts in chemical processes. ... more There are many advantages to using ionic liquids as solvents or catalysts in chemical processes. Their non-volatile characteristic and high cost, however, can pose economic, environmental, and long-term health concerns. As such, the recovery and recycling of ionic liquids have become essential to mitigate their environmental impact and to reduce costs. Numerous recovery and recycling methods have been reported, including distillation, extraction, membrane separation (a.k.a. filtration), adsorption, crystallization, gravity, and electrochemical separation. Whereas most of these methods recover both cations and anions of the ionic liquid as ion pairs, recycling methods such as single-phase ion exchange or mixed-ion exchange/non-ionic adsorption methods recover only one of the ionic liquid ions, typically the cation. These methods are frequently used for the recycling of ionic liquids having simple anions such as chloride or acetate, but are seldom employed for ionic liquids consisting...
Journal of Chromatography A, Nov 1, 2005
The chemometric resolution and quantification of overlapped peaks from comprehensive two-dimensio... more The chemometric resolution and quantification of overlapped peaks from comprehensive two-dimensional (2D) liquid chromatography (LC × LC) data are demonstrated. The LC × LC data is produced from an in-house LC × LC analyzer that couples an anion-exchange column via a multi-port valve with a reversed-phase column connected to a UV absorbance detector. Three test mixtures, each containing a target analyte, are subjected to partial LC × LC separations to simulate likely cases of signal overlap. The resulting unresolved target-analyte signals are then analyzed by the standard-addition method and two chemometric methods. The LC × LC analyses of a test mixture and its corresponding standard-addition mixture results in two data matrices, one for each mixture. The stacking of these two data matrices produces a data structure that can then be analyzed by trilinear chemometric methods. One method, the generalized rank annihilation method (GRAM), uses a non-iterative eigenvalue-based approach to mathematically resolve overlapped trilinear signals. The other method, parallel factor analysis (PARAFAC), uses an iterative approach to resolve trilinear signals by the optimization of initial estimates using alternating least squares and signal constraints. In this paper, GRAM followed by PARAFAC analysis is shown to produce better qualitative and quantitative results than using each method separately. For instance, for all three test mixtures, the GRAM-PARAFAC approach improved quantitative accuracy by at least a factor of 4 and quantitative precision by more than 2 when compared to GRAM alone. This paper also introduces a new means of correcting run-to-run retention time shifts in comprehensive 2D chromatographic data.
Acta Crystallographica Section E: Crystallographic Communications, Jul 4, 2019
Five new crystal structures of perfluoropyridine substituted in the 4-position with phenoxy, 4-br... more Five new crystal structures of perfluoropyridine substituted in the 4-position with phenoxy, 4-bromophenoxy, naphthalen-2-yloxy, 6-bromonaphthalen-2yloxy, and 4,4 0-biphenoxy are reported, viz. 2,3,5,6-tetrafluoro-4-phenoxypyridine, C 11 H 5 F 4 NO (I), 4-(4-bromophenoxy)-2,3,5,6-tetrafluoropyridine, C 11 H 4 BrF 4 NO (II), 2,3,5,6-tetrafluoro-4-[(naphthalen-2-yl)oxy]pyridine, C 15 H 7 F 4 NO (III), 4-[(6-bromonaphthalen-2-yl)oxy]-2,3,5,6-tetrafluoropyridine, C 15 H 6 BrF 4 NO (IV), and 2,2 0-bis[(perfluoropyridin-4-yl)oxy]-1,1 0-biphenyl, C 22 H 8 F 8 N 2 O 2 (V). The dihedral angles between the aromatic ring systems in I-IV are 78.74 (8), 56.35 (8), 74.30 (7), and 64.34 (19) , respectively. The complete molecule of V is generated by a crystallographic twofold axis: the dihedral angle between the pyridine ring and adjacent phenyl ring is 80.89 (5) and the equivalent angle between the biphenyl rings is 27.30 (5). In each crystal, the packing is driven by C-HÁ Á ÁF interactions, along with a variety of C-FÁ Á Á, C-HÁ Á Á, C-BrÁ Á ÁN, C-HÁ Á ÁN, and C-BrÁ Á Á contacts. Hirshfeld surface analysis was conducted to aid in the visualization of these various influences on the packing. research communications
ECS Meeting Abstracts, 2006
not Available.
Kluwer Academic Publishers eBooks, Dec 2, 2005
Industrial & Engineering Chemistry Research, Apr 15, 2008
Industrial & Engineering Chemistry Research, May 26, 2009
Ionic liquids have the potential for being ideal alternatives for organic solvents in chemical wa... more Ionic liquids have the potential for being ideal alternatives for organic solvents in chemical warfare agent reactions and demilitarization processes. They are considered to be an excellent substitute, because of their extraordinarily wide liquid range, low melting points, chemical ...
University of Colorado Colorado Springs. Kraemer Family Library, May 1, 2018
Journal of Fluorine Chemistry, 2020
Macromolecular Chemistry and Physics, 2020
Two new trifunctional alkene monomers based on the highly modular perfluoropyridine scaffold are ... more Two new trifunctional alkene monomers based on the highly modular perfluoropyridine scaffold are synthesized with an aliphatic and an aromatic moiety, 4‐penten‐1‐ol and eugenol, respectively. The monomers are the basis for thiol‐ene thermoset materials, formulated against a difunctional or trifunctional thiol. Systems based on these novel monomers have a wide range of thermal properties, with glass transition temperatures (Tgs) spanning from −42 to 21 °C. Mixed systems obey the Fox equation, and Tgs of the mixtures can be tuned to specific values in that range. Thermal degradation temperatures follow a similar trend, with decomposition temperatures ranging from 274 to 348 °C in nitrogen with varying compositions having tailorability therein. This new class of semifluorinated thermoset materials with tunable thermal properties has several potential applications within the aerospace industry, such as sealants and coatings, where stability and survivability at high temperatures in hars...
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this
Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is est... more Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 12 December 2015 2. RE...
Journal of Fluorine Chemistry, 2019
The Journal of Physical Chemistry A, 2019
Separations, 2019
There are many advantages to using ionic liquids as solvents or catalysts in chemical processes. ... more There are many advantages to using ionic liquids as solvents or catalysts in chemical processes. Their non-volatile characteristic and high cost, however, can pose economic, environmental, and long-term health concerns. As such, the recovery and recycling of ionic liquids have become essential to mitigate their environmental impact and to reduce costs. Numerous recovery and recycling methods have been reported, including distillation, extraction, membrane separation (a.k.a. filtration), adsorption, crystallization, gravity, and electrochemical separation. Whereas most of these methods recover both cations and anions of the ionic liquid as ion pairs, recycling methods such as single-phase ion exchange or mixed-ion exchange/non-ionic adsorption methods recover only one of the ionic liquid ions, typically the cation. These methods are frequently used for the recycling of ionic liquids having simple anions such as chloride or acetate, but are seldom employed for ionic liquids consisting...