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4. Silver 4,4′-Vinylenedipyridine Coordination Polymers: Linker Effects on Formation Thermodynamics and Anion Exchange

Author

Barnett, Jeremy L., Wenger, John S., Getahun, Addis, Johnstone, Timothy C., and Oliver, Scott R. J.

Abstract

Four new and one previously reported silver 4,4′-vinylenedipyridine (Vpe) coordination polymers were tested as anion exchange materials to assess their potential for pollutant sequestration and compared to analogous silver 4,4′-bipyridine (bipy) coordination polymers. The materials were synthesized using nitrate, tetrafluoroborate, perchlorate, perrhenate, or chromate as the anion to produce cationic coordination polymers with solubilities ranging from 0.0137(7) to 0.21(5) mM. These values are much lower than silver bipy coordination polymers [0.045(3) to 5.5(5) mM] and agree with thermochemical calculations. [Ag(Vpe)+][BF4–], [Ag2(Vpe)2.52+][CrO42–]·5H2O, and [Ag(Vpe)+][ReO4–]·2H2O structures are reported. Perrhenate and chromate ions in an equimolar solution were fully adsorbed by [Ag(Vpe)+][NO3–]·3H2O [620(2) and 137.1(6) mg/g, respectively] as well as by [Ag(Vpe)+][BF4–] [661.8(3) and 190(3) mg/g, respectively] via anion exchange. DFT calculations show that torsional energetics play a significant role in the formation thermodynamics by reducing the energy cost by as much as 4.8 kJ/mol when bipy is replaced with Vpe in silver-based coordination polymers. The results obtained with the flat Vpe ligand highlight the potential role of coordination polymers in practical anion exchange.

Published
2025
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7. Perhalogenated Anions as Structure Directing Agents of Cationic Coordination Polymers

Author

Lofgren, Kevin C., Fusari, Kellii J., Droege, Daniel G., Barnett, Jeremy L., Johnstone, Timothy C., and Oliver, Scott R. J.

Abstract

We investigate the synthesis of coordination polymers (CPs) comprising silver cations, 4,4′-bipyridine and the charge-balancing perhalogenated acetate anions trifluoroacetate (CF3COO–), trichloroacetate (CCl3COO–), tribromoacetate (CBr3COO–) or triiodoacetate (CI3COO–). The syntheses involved anion exchange using the starting CP silver 4,4′-bipyridine acetate. Multianalytical characterization was conducted using powder X-ray diffraction, single crystal X-ray diffraction, optical microscopy and thermogravimetric analysis. Our findings revealed that CPs were formed with CF3COO–or CCl3COO–as the charge-balancing anion and exhibited notable stability. In contrast, reactions with CBr3COO–and CI3COO–showed that the starting anion undergoes decomposition to bromide, iodide or triiodide before being incorporated into the resulting material. This study sheds light on the interactions between perhalogenated anions and CPs and the potential for the use of CPs in the removal of perhalogenated “forever chemicals.”

Published
2024
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13. Invertebrate Responses to the Management of Genetically Modified Herbicide-Tolerant and Conventional Spring Crops. II. Within-Field Epigeal and Aerial Arthropods

Author

Haughton, A. J., Champion, G. T., Hawes, C., Heard, M. S., Brooks, D. R., Bohan, D. A., Clark, S. J., Dewar, A. M., Firbank, L. G., Osborne, J. L., Perry, J. N., Rothery, P., Roy, D. B., Scott, R. J., Woiwod, I. P., Birchall, C., Skellern, M. P., Walker, J. H., Baker, P., Browne, E. L., Dewar, A. J. G., Garner, B. H., Haylock, L. A., Horne, S. L., Mason, N. S., Sands, R. J. N., and Walker, M. J.

Published
2003

14. Invertebrate Responses to the Management of Genetically Modified Herbicide-Tolerant and Conventional Spring Crops. I. Soil-Surface-Active Invertebrates

Author

Brooks, D. R., Bohan, D. A., Champion, G. T., Haughton, A. J., Hawes, C., Heard, M. S., Clark, S. J., Dewar, A. M., Firbank, L. G., Perry, J. N., Rothery, P., Scott, R. J., Woiwod, I. P., Birchall, C., Skellern, M. P., Walker, J. H., Baker, P., Bell, D., Browne, E. L., Dewar, A. J. G., Fairfax, C. M., Garner, B. H., Haylock, L. A., Horne, S. L., Hulmes, S. E., Mason, N. S., Norton, L. R., Nuttall, P., Randle, Z., Rossall, M. J., Sands, R. J. N., Singer, E. J., and Walker, M. J.

Published
2003

28. A crystal-structural study of Pauling–Corey rippled sheets

Author

Ariel J. Kuhn, Beatriz Ehlke, Timothy C. Johnstone, Scott R. J. Oliver, and Jevgenij A. Raskatov

Subjects
General Chemistry
Abstract

Following the seminal theoretical work on the pleated β-sheet published by Pauling and Corey in 1951, the rippled β-sheet was hypothesized by the same authors in 1953. In the pleated β-sheet the interacting β-strands have the same chirality, whereas in the rippled β-sheet the interacting β-strands are mirror-images. Unlike with the pleated β-sheet that is now common textbook knowledge, the rippled β-sheet has been much slower to evolve. Much of the experimental work on rippled sheets came from groups that study aggregating racemic peptide systems over the course of the past decade. This includes MAX1/DMAX hydrogels (Schneider), L/D-KFE8 aggregating systems (Nilsson), and racemic Amyloid β mixtures (Raskatov). Whether a racemic peptide mixture is "ripple-genic" (

Published
2022
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33. GWAS for executive function and processing speed suggests involvement of the CADM2 gene

Author

Ibrahim-Verbaas, C A, Bressler, J, Debette, S, Schuur, M, Smith, A V, Bis, J C, Davies, G, Trompet, S, Smith, J A, Wolf, C, Chibnik, L B, Liu, Y, Vitart, V, Kirin, M, Petrovic, K, Polasek, O, Zgaga, L, Fawns-Ritchie, C, Hoffmann, P, Karjalainen, J, Lahti, J, Llewellyn, D J, Schmidt, C O, Mather, K A, Chouraki, V, Sun, Q, Resnick, S M, Rose, L M, Oldmeadow, C, Stewart, M, Smith, B H, Gudnason, V, Yang, Q, Mirza, S S, Jukema, J W, deJager, P L, Harris, T B, Liewald, D C, Amin, N, Coker, L H, Stegle, O, Lopez, O L, Schmidt, R, Teumer, A, Ford, I, Karbalai, N, Becker, J T, Jonsdottir, M K, Au, R, Fehrmann, R S N, Herms, S, Nalls, M, Zhao, W, Turner, S T, Yaffe, K, Lohman, K, van Swieten, J C, Kardia, S L R, Knopman, D S, Meeks, W M, Heiss, G, Holliday, E G, Schofield, P W, Tanaka, T, Stott, D J, Wang, J, Ridker, P, Gow, A J, Pattie, A, Starr, J M, Hocking, L J, Armstrong, N J, McLachlan, S, Shulman, J M, Pilling, L C, Eiriksdottir, G, Scott, R J, Kochan, N A, Palotie, A, Hsieh, Y-C, Eriksson, J G, Penman, A, Gottesman, R F, Oostra, B A, Yu, L, DeStefano, A L, Beiser, A, Garcia, M, Rotter, J I, Nöthen, M M, Hofman, A, Slagboom, P E, Westendorp, R G J, Buckley, B M, Wolf, P A, Uitterlinden, A G, Psaty, B M, Grabe, H J, Bandinelli, S, Chasman, D I, Grodstein, F, Räikkönen, K, Lambert, J-C, Porteous, D J, Price, J F, Sachdev, P S, Ferrucci, L, Attia, J R, Rudan, I, Hayward, C, Wright, A F, Wilson, J F, Cichon, S, Franke, L, Schmidt, H, Ding, J, de Craen, A J M, Fornage, M, Bennett, D A, Deary, I J, Ikram, M A, Launer, L J, Fitzpatrick, A L, Seshadri, S, van Duijn, C M, and Mosley, T H

Published
2016
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34. Structural diversity of four lanthanide metal–organic frameworks based on 2,6-naphthalenedicarboxylate: synthesis, structures and photoluminescent properties

Author

Eric W. Reinheimer, Scott R. J. Oliver, Honghan Fei, Xueling Song, Pierre Le Magueres, Ana R.K. Chatenever, and Beatriz Ehlke

Subjects
Lanthanide, Crystallography, Materials science, Photoluminescence, Coordination number, Thermal decomposition, Infrared spectroscopy, General Materials Science, Metal-organic framework, General Chemistry, Crystal structure, Condensed Matter Physics, Luminescence
Abstract

We report the crystal structures of four different neutral lanthanide (Ln = La, Nd, Eu and Gd) metal–organic frameworks based on the organic linker 2,6-naphthalenedicarboxylate (NDC). The materials are three-dimensional and crystallize in three distinct topologies, with distinct bonding modes of NDC and lanthanide coordination numbers ranging from seven to nine and varying geometry. We denote our materials SLUG-49 [La6(NDC)9(DMF)3·6 DMF], -50 [Nd2(NDC)3O(DMF)2], -51 [Eu2(NDC)3(DMF)2·DMF], and -52 [Gd4(NDC)6(DMF)4] (DMF = N,N-dimethylformamide). The structures exhibit similar thermal decomposition profiles and infrared spectra. The Eu(III)-based material exhibits a sharp red-orange luminescence at 613 nm with a quantum efficiency of 3.56%.

Published
2021
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37. Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53 949)

Author

Davies, G, Armstrong, N, Bis, J C, Bressler, J, Chouraki, V, Giddaluru, S, Hofer, E, Ibrahim-Verbaas, C A, Kirin, M, Lahti, J, van der Lee, S J, Le Hellard, S, Liu, T, Marioni, R E, Oldmeadow, C, Postmus, I, Smith, A V, Smith, J A, Thalamuthu, A, Thomson, R, Vitart, V, Wang, J, Yu, L, Zgaga, L, Zhao, W, Boxall, R, Harris, S E, Hill, W D, Liewald, D C, Luciano, M, Adams, H, Ames, D, Amin, N, Amouyel, P, Assareh, A A, Au, R, Becker, J T, Beiser, A, Berr, C, Bertram, L, Boerwinkle, E, Buckley, B M, Campbell, H, Corley, J, De Jager, P L, Dufouil, C, Eriksson, J G, Espeseth, T, Faul, J D, Ford, I, Scotland, Generation, Gottesman, R F, Griswold, M E, Gudnason, V, Harris, T B, Heiss, G, Hofman, A, Holliday, E G, Huffman, J, Kardia, S L R, Kochan, N, Knopman, D S, Kwok, J B, Lambert, J-C, Lee, T, Li, G, Li, S-C, Loitfelder, M, Lopez, O L, Lundervold, A J, Lundqvist, A, Mather, K A, Mirza, S S, Nyberg, L, Oostra, B A, Palotie, A, Papenberg, G, Pattie, A, Petrovic, K, Polasek, O, Psaty, B M, Redmond, P, Reppermund, S, Rotter, J I, Schmidt, H, Schuur, M, Schofield, P W, Scott, R J, Steen, V M, Stott, D J, van Swieten, J C, Taylor, K D, Trollor, J, Trompet, S, Uitterlinden, A G, Weinstein, G, Widen, E, Windham, B G, Jukema, J W, Wright, A F, Wright, M J, Yang, Q, Amieva, H, Attia, J R, Bennett, D A, Brodaty, H, de Craen, A J M, Hayward, C, Ikram, M A, Lindenberger, U, Nilsson, L-G, Porteous, D J, Räikkönen, K, Reinvang, I, Rudan, I, Sachdev, P S, Schmidt, R, Schofield, P R, Srikanth, V, Starr, J M, Turner, S T, Weir, D R, Wilson, J F, van Duijn, C, Launer, L, Fitzpatrick, A L, Seshadri, S, Mosley, Jr, T H, and Deary, I J

Published
2015
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38. Evaluation of epigenetic methylation biomarkers for the detection of colorectal cancer using droplet digital PCR.

Author

Petit, J., Carroll, G., Zhao, J., Roper, E., Pockney, P., and Scott, R. J.

Subjects
COLORECTAL cancer, EARLY detection of cancer, METHYLATION, EPIGENETICS, DNA methylation, CIRCULATING tumor DNA
Abstract

Colorectal cancer (CRC) is the third most common cancer worldwide. Screening programs allow early diagnosis and have improved the clinical management of this disease. Aberrant DNA methylation is increasingly being explored as potential biomarkers for many types of cancers. In this study we investigate the methylation of ten target genes in 105 CRC and paired normal adjacent colonic tissue samples using a MethylLight droplet digital PCR (ML-ddPCR) assay. Receiver operator characteristic (ROC) curves were used to determine the diagnostic performance of all target genes individually and in combination. All 515 different combinations of genes showed significantly higher levels of methylation in CRC tissue. The combination of multiple target genes into a single test generally resulted in greater diagnostic accuracy when compared to single target genes. Our data confirms that ML-ddPCR is able to reliably detect significant differences in DNA methylation between CRC tissue and normal adjacent colonic tissue in a specific selection of target genes. [ABSTRACT FROM AUTHOR]

Published
2023
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41. Isomorphous Lanthanide Metal–Organic Frameworks Based on Biphenyldicarboxylate: Synthesis, Structure, and Photoluminescent Properties

Author

Scott R. J. Oliver, Pierre LeMagueres, Stanley J. Wang, Honghan Fei, Joe E. Matsuoka, Ana R.K. Chatenever, Eric W. Reinheimer, Xueling Song, and Louis R. Warne

Subjects
Lanthanide, Crystallography, Materials science, Photoluminescence, 010405 organic chemistry, General Materials Science, Metal-organic framework, General Chemistry, 010402 general chemistry, Condensed Matter Physics, 01 natural sciences, 0104 chemical sciences
Abstract

We report the structures of six anionic, isomorphous metal–organic frameworks [Ln(bpdc)2–][NH2(CH3)2+], where Ln = La, Ce, Nd, Eu, Gd, Er, and bpdc2– = biphenyl-4,4′-dicarboxylate = –O2C(C6H4)2CO2–...

Published
2019
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42. A Cationic Silver Pyrazine Coordination Polymer with High Capacity Anion Uptake from Water

Author

Scott R. J. Oliver, Eaindar Soe, and Beatriz Ehlke

Subjects
Anions, Silver, Perrhenate, Ion exchange, Pyrazine, Polymers, Coordination polymer, Inorganic chemistry, Permanganate, Cationic polymerization, Water, Portable water purification, General Chemistry, 010501 environmental sciences, 01 natural sciences, chemistry.chemical_compound, chemistry, Pyrazines, Environmental Chemistry, Carboxylate, 0105 earth and related environmental sciences
Abstract

We report the first example of linker modification for an N-donor Ag-based cationic material while maintaining and in some cases increasing the anion exchange capacity. Cationic silver(I) pyrazine nitrate selectively traps harmful oxo-anions from water such as permanganate, perrhenate and a variety of α,ω-alkanedicarboxylates. We chose these anions as initial examples of exchange for potential water purification. The host-guest interaction between the cationic layers of π-stacked silver pyrazine polymers and the incoming/outgoing interlamellar anions allows for the exchange. The exchange capacity over 24 h reached 435 and 818 mg/g for permanganate and perrhenate, respectively, a record for a crystalline metal-organic material and over five times the exchange capacity compared to commercial resin. The material also undergoes organic exchange as an analog for pharmaceutical waste, some of which have a carboxylate functionality at the neutral pH range typical of natural water sources. Both the as-synthesized and exchanged materials are characterized by a variety of analytical techniques.

Published
2019
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