Articles de revues : « Paramagnetic solid state NMR »

1

Bertmer, Marko. « Paramagnetic solid-state NMR of materials ». Solid State Nuclear Magnetic Resonance 81 (février 2017) : 1–7. http://dx.doi.org/10.1016/j.ssnmr.2016.10.006.

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Tang, Ming, et Dennis Lam. « Paramagnetic solid-state NMR of proteins ». Solid State Nuclear Magnetic Resonance 103 (novembre 2019) : 9–16. http://dx.doi.org/10.1016/j.ssnmr.2019.101621.

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Li, Wenyu, Qianyun Zhang, Jonas J. Joos, Philippe F. Smet et Jörn Schmedt auf der Günne. « Blind spheres of paramagnetic dopants in solid state NMR ». Physical Chemistry Chemical Physics 21, n^o 19 (2019) : 10185–94. http://dx.doi.org/10.1039/c9cp00953a.

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Luchinat, Claudio, Giacomo Parigi, Enrico Ravera et Mauro Rinaldelli. « Solid-State NMR Crystallography through Paramagnetic Restraints ». Journal of the American Chemical Society 134, n^o 11 (8 mars 2012) : 5006–9. http://dx.doi.org/10.1021/ja210079n.

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Heise, Henrike, Frank H. Köhler et Xiulan Xie. « Solid-State NMR Spectroscopy of Paramagnetic Metallocenes ». Journal of Magnetic Resonance 150, n^o 2 (juin 2001) : 198–206. http://dx.doi.org/10.1006/jmre.2001.2343.

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Pell, Andrew J., et Guido Pintacuda. « Broadband solid-state MAS NMR of paramagnetic systems ». Progress in Nuclear Magnetic Resonance Spectroscopy 84-85 (février 2015) : 33–72. http://dx.doi.org/10.1016/j.pnmrs.2014.12.002.

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Pell, Andrew J., Guido Pintacuda et Clare P. Grey. « Paramagnetic NMR in solution and the solid state ». Progress in Nuclear Magnetic Resonance Spectroscopy 111 (avril 2019) : 1–271. http://dx.doi.org/10.1016/j.pnmrs.2018.05.001.

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Li, Wenyu, Vinicius R. Celinski, Johannes Weber, Nathalie Kunkel, Holger Kohlmann et Jörn Schmedt auf der Günne. « Homogeneity of doping with paramagnetic ions by NMR ». Physical Chemistry Chemical Physics 18, n^o 14 (2016) : 9752–57. http://dx.doi.org/10.1039/c5cp07606d.

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Cheetham, A. K., C. M. Dobson, C. P. Grey et R. J. B. Jakeman. « Paramagnetic shift probes in high-resolution solid-state NMR ». Nature 328, n^o 6132 (août 1987) : 706–7. http://dx.doi.org/10.1038/328706a0.

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Sengupta, Ishita, Philippe S. Nadaud et Christopher P. Jaroniec. « Protein Structure Determination with Paramagnetic Solid-State NMR Spectroscopy ». Accounts of Chemical Research 46, n^o 9 (6 mars 2013) : 2117–26. http://dx.doi.org/10.1021/ar300360q.

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Tuel, A., L. Canesson et J. C. Volta. « Investigation of paramagnetic catalysts by solid state NMR spectroscopy ». Colloids and Surfaces A : Physicochemical and Engineering Aspects 158, n^o 1-2 (novembre 1999) : 97–106. http://dx.doi.org/10.1016/s0927-7757(99)00136-3.

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Blümel, Janet, Martin Herker, Wolfgang Hiller et Frank H. Köhler. « Study of Paramagnetic Chromocenes by Solid-State NMR Spectroscopy ». Organometallics 15, n^o 16 (janvier 1996) : 3474–76. http://dx.doi.org/10.1021/om960042p.

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ARSHAD, M. A., J. A. RIPMEESTER et M. SCHNITZER. « ATTEMPTS TO IMPROVE SOLID STATE 13C NMR SPECTRA OF WHOLE MINERAL SOILS ». Canadian Journal of Soil Science 68, n^o 3 (1 août 1988) : 593–602. http://dx.doi.org/10.4141/cjss88-057.

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This study describes a number of different preparation techniques for recording solid state 13C NMR spectra of whole mineral soils. Removal of paramagnetic Fe3+ improves the quality of 13C NMR spectra of whole soils and of particle size fractions. The C:Fe ratio appears to be an important indicator for obtaining satisfactory 13C NMR spectra of whole soils and fractions separated from them. If the C:Fe ratio is >> 1, the quality of the spectrum will be good; if the ratio is > 1, a reasonable spectrum will be obtained, but if the ratio is < 1, the spectrum will be poor. Organic-matter-rich soil and particle size fractions separated by a flotation technique produce well-defined 13C NMR spectra, typical of humic materials. Reduction of C-enriched fractions with sodium dithionite and stannous chloride improves the spectral resolution. The data presented herein show that satisfactory solid state 13C NMR spectra can be run on untreated soil particle size fractions, non-magnetic portions of whole soils, and fractions enriched in soil organic matter by flotation, especially after chemical reduction. Key words: 13C NMR spectroscopy, paramagnetic mineral separation

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Jaroniec, Christopher P. « Structural studies of proteins by paramagnetic solid-state NMR spectroscopy ». Journal of Magnetic Resonance 253 (avril 2015) : 50–59. http://dx.doi.org/10.1016/j.jmr.2014.12.017.

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Flambard, Alexandrine, Laurent Ruhlmann, Jacqueline Canny et René Thouvenot. « Solution and solid-state 31P NMR study of paramagnetic polyoxometalates ». Comptes Rendus Chimie 11, n^o 4-5 (avril 2008) : 415–22. http://dx.doi.org/10.1016/j.crci.2007.08.009.

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Kervern, Gwendal, Guido Pintacuda et Lyndon Emsley. « Fast adiabatic pulses for solid-state NMR of paramagnetic systems ». Chemical Physics Letters 435, n^o 1-3 (février 2007) : 157–62. http://dx.doi.org/10.1016/j.cplett.2006.12.056.

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Pell, Andrew J., et Guido Pintacuda. « ChemInform Abstract : Broadband Solid-State MAS NMR of Paramagnetic Systems ». ChemInform 46, n^o 46 (27 octobre 2015) : no. http://dx.doi.org/10.1002/chin.201546299.

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Whittaker, Christopher A. P., Simon G. Patching, Mikael Esmann et David A. Middleton. « Ligand orientation in a membrane-embedded receptor site revealed by solid-state NMR with paramagnetic relaxation enhancement ». Organic & ; Biomolecular Chemistry 13, n^o 9 (2015) : 2664–68. http://dx.doi.org/10.1039/c4ob02427c.

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Prosser, R. Scott, V. B. Volkov et I. V. Shiyanovskaya. « Solid-state NMR studies of magnetically aligned phospholipid membranes : taming lanthanides for membrane protein studies ». Biochemistry and Cell Biology 76, n^o 2-3 (1 mai 1998) : 443–51. http://dx.doi.org/10.1139/o98-058.

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The addition of lanthanides (Tm3+, Yb3+, Er3+, or Eu3+) to a solution of long-chain phospholipids such as dimyristoylphosphatidylcholine (DMPC) and short-chain phospholipids such as dihexanoylphosphatidylcholine (DHPC) is known to result in a bilayer phase in which the average bilayer normal aligns parallel to an applied magnetic field. Lanthanide-doped bilayers have enormous potential for the study of membrane proteins by solid-state NMR, low-angle diffraction, and a variety of optical spectroscopic techniques. However, the addition of lanthanides poses certain challenges to the NMR spectroscopist: coexistence of an isotropic phase and hysteresis effects, direct binding of the paramagnetic ion to the peptide or protein of interest, and severe paramagnetic shifts and line broadening. Lower water concentrations and larger DMPC/DHPC ratios than those typically used in bicelles consistently yield a single oriented bilayer phase that is stable over a wide range of temperature (~35-90°C). Among the above choice of lanthanides, Yb3+ is found to give minimal paramagnetic shifts and line broadening at acceptably low concentrations necessary for alignment (i.e., Yb3+/DMPC mole ratios equal to or greater than 0.01). Finally, the addition of a phospholipid chelate, 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine - diethylenetriaminepentaacetic acid, is observed to significantly reduce paramagnetic broadening and presumably prevent direct association of the peptide with the lanthanide ions.Key words: lanthanide, solid-state NMR, model membrane, membrane protein structure.

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Hua, Carol, Stone Woo, Aditya Rawal, Floriana Tuna, James M. Hook, David Collison et Deanna M. D'Alessandro. « Redox-State Dependent Spectroscopic Properties of Porous Organic Polymers Containing Furan, Thiophene, and Selenophene ». Australian Journal of Chemistry 70, n^o 11 (2017) : 1227. http://dx.doi.org/10.1071/ch17335.

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A series of electroactive triarylamine porous organic polymers (POPs) with furan, thiophene, and selenophene (POP-O, POP-S, and POP-Se) linkers have been synthesised and their electronic and spectroscopic properties investigated as a function of redox state. Solid state NMR provided insight into the structural features of the POPs, while in situ solid state Vis-NIR and electron paramagnetic resonance spectroelectrochemistry showed that the distinct redox states in POP-S could be reversibly accessed. The development of redox-active porous organic polymers with heterocyclic linkers affords their potential application as stimuli responsive materials in gas storage, catalysis, and as electrochromic materials.

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21

Balayssac, Stéphane, Ivano Bertini, Moreno Lelli, Claudio Luchinat et Massimiliano Maletta. « Paramagnetic Ions Provide Structural Restraints in Solid-State NMR of Proteins ». Journal of the American Chemical Society 129, n^o 8 (février 2007) : 2218–19. http://dx.doi.org/10.1021/ja068105a.

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Ishihara, Shinsuke, Kenzo Deguchi, Hiroaki Sato, Masatoshi Takegawa, Eisaku Nii, Shinobu Ohki, Kenjiro Hashi et al. « Multinuclear solid-state NMR spectroscopy of a paramagnetic layered double hydroxide ». RSC Advances 3, n^o 43 (2013) : 19857. http://dx.doi.org/10.1039/c3ra44231d.

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Mizuno, Motohiro, Naohisa Itakura et Kazunaka Endo. « Effects of strong paramagnetic interactions on solid-state deuterium NMR spectra ». Chemical Physics Letters 416, n^o 4-6 (décembre 2005) : 358–63. http://dx.doi.org/10.1016/j.cplett.2005.09.070.

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Koltover, Vitaly K., John W. Logan, Henrike Heise, Vyacheslav P. Bubnov, Yakov I. Estrin, Ivan E. Kareev, Vera P. Lodygina et Alexander Pines. « Diamagnetic Clusters of Paramagnetic Endometallofullerenes : A Solid-State MAS NMR Study ». Journal of Physical Chemistry B 108, n^o 33 (août 2004) : 12450–55. http://dx.doi.org/10.1021/jp048610z.

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Jaipuria, Garima, Karin Giller, Andrei Leonov, Stefan Becker et Markus Zweckstetter. « Insights into Cholesterol/Membrane Protein Interactions Using Paramagnetic Solid-State NMR ». Chemistry - A European Journal 24, n^o 66 (5 novembre 2018) : 17606–11. http://dx.doi.org/10.1002/chem.201804550.

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Schmedt auf der Günne, Jörn. « Spin-Polarized Structures and Solid-State NMR Spectroscopy of Paramagnetic Compounds ». Angewandte Chemie International Edition 48, n^o 19 (27 avril 2009) : 3401–3. http://dx.doi.org/10.1002/anie.200900360.

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Bakhmutov, Vladimir I. « Strategies for Solid-State NMR Studies of Materials : From Diamagnetic to Paramagnetic Porous Solids ». Chemical Reviews 111, n^o 2 (9 février 2011) : 530–62. http://dx.doi.org/10.1021/cr100144r.

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Andersen, Anders B. A., Ari Pyykkönen, Hans Jørgen Aa Jensen, Vickie McKee, Juha Vaara et Ulla Gro Nielsen. « Remarkable reversal of 13C-NMR assignment in d1, d2 compared to d8, d9 acetylacetonate complexes : analysis and explanation based on solid-state MAS NMR and computations ». Physical Chemistry Chemical Physics 22, n^o 15 (2020) : 8048–59. http://dx.doi.org/10.1039/d0cp00980f.

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Lee, Jeongjae, Ieuan D. Seymour, Andrew J. Pell, Siân E. Dutton et Clare P. Grey. « A systematic study of 25Mg NMR in paramagnetic transition metal oxides : applications to Mg-ion battery materials ». Physical Chemistry Chemical Physics 19, n^o 1 (2017) : 613–25. http://dx.doi.org/10.1039/c6cp06338a.

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Zehnder, Johannes, Riccardo Cadalbert, Maxim Yulikov, Georg Künze et Thomas Wiegand. « Paramagnetic spin labeling of a bacterial DnaB helicase for solid-state NMR ». Journal of Magnetic Resonance 332 (novembre 2021) : 107075. http://dx.doi.org/10.1016/j.jmr.2021.107075.

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Maltsev, Sergey, Stephen M. Hudson, Indra D. Sahu, Lishan Liu et Gary A. Lorigan. « Solid-State NMR 31P Paramagnetic Relaxation Enhancement Membrane Protein Immersion Depth Measurements ». Journal of Physical Chemistry B 118, n^o 16 (11 avril 2014) : 4370–77. http://dx.doi.org/10.1021/jp500267y.

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Bertini, Ivano, Lyndon Emsley, Moreno Lelli, Claudio Luchinat, Jiafei Mao et Guido Pintacuda. « Ultrafast MAS Solid-State NMR Permits Extensive13C and1H Detection in Paramagnetic Metalloproteins ». Journal of the American Chemical Society 132, n^o 16 (28 avril 2010) : 5558–59. http://dx.doi.org/10.1021/ja100398q.

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Maron, Sébastien, Nadège Ollier, Thierry Gacoin et Géraldine Dantelle. « Determination of paramagnetic concentrations inside a diamagnetic matrix using solid-state NMR ». Physical Chemistry Chemical Physics 19, n^o 19 (2017) : 12175–84. http://dx.doi.org/10.1039/c7cp00451f.

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Tang, Ming, Deborah A. Berthold et Chad M. Rienstra. « Solid-State NMR of a Large Membrane Protein by Paramagnetic Relaxation Enhancement ». Journal of Physical Chemistry Letters 2, n^o 14 (12 juillet 2011) : 1836–41. http://dx.doi.org/10.1021/jz200768r.

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Chu, Shidong, Sergey Maltsev, A. H. Emwas et Gary A. Lorigan. « Solid-state NMR paramagnetic relaxation enhancement immersion depth studies in phospholipid bilayers ». Journal of Magnetic Resonance 207, n^o 1 (novembre 2010) : 89–94. http://dx.doi.org/10.1016/j.jmr.2010.08.012.

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Balayssac, S., I. Bertini, A. Bhaumik, M. Lelli et C. Luchinat. « Paramagnetic shifts in solid-state NMR of proteins to elicit structural information ». Proceedings of the National Academy of Sciences 105, n^o 45 (6 novembre 2008) : 17284–89. http://dx.doi.org/10.1073/pnas.0708460105.

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Sengupta, Ishita, Philippe S. Nadaud, Jonathan J. Helmus, Charles D. Schwieters et Christopher P. Jaroniec. « Protein fold determined by paramagnetic magic-angle spinning solid-state NMR spectroscopy ». Nature Chemistry 4, n^o 5 (18 mars 2012) : 410–17. http://dx.doi.org/10.1038/nchem.1299.

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Perez, Alberto, Kari Gaalswyk, Christopher P. Jaroniec et Justin L. MacCallum. « High Accuracy Protein Structures from Minimal Sparse Paramagnetic Solid‐State NMR Restraints ». Angewandte Chemie 131, n^o 20 (17 avril 2019) : 6636–40. http://dx.doi.org/10.1002/ange.201811895.

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Perez, Alberto, Kari Gaalswyk, Christopher P. Jaroniec et Justin L. MacCallum. « High Accuracy Protein Structures from Minimal Sparse Paramagnetic Solid‐State NMR Restraints ». Angewandte Chemie International Edition 58, n^o 20 (13 mai 2019) : 6564–68. http://dx.doi.org/10.1002/anie.201811895.

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Stebbins, Jonathan F., Ryan J. McCarty et Aaron C. Palke. « Solid-state NMR and short-range order in crystalline oxides and silicates : a new tool in paramagnetic resonances ». Acta Crystallographica Section C Structural Chemistry 73, n^o 3 (6 février 2017) : 128–36. http://dx.doi.org/10.1107/s2053229616015606.

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Most applications of high-resolution NMR to questions of short-range order/disorder in inorganic materials have been made in systems where ions with unpaired electron spins are of negligible concentration, with structural information extracted primarily from chemical shifts, quadrupolar coupling parameters, and nuclear dipolar couplings. In some cases, however, the often-large additional resonance shifts caused by interactions between unpaired electron and nuclear spins can provide unique new structural information in materials with contents of paramagnetic cations ranging from hundreds of ppm to several per cent and even higher. In this brief review we focus on recent work on silicate, phosphate, and oxide materials with relatively low concentrations of paramagnetic ions, where spectral resolution can remain high enough to distinguish interactions between NMR-observed nuclides and one or more magnetic neighbors in different bonding configurations in the first, second, and even farther cation shells. We illustrate the types of information available, some of the limitations of this approach, and the great prospects for future experimental and theoretical work in this field. We give examples for the effects of paramagnetic transition metal, lanthanide, and actinide cation substitutions in simple oxides, pyrochlore, zircon, monazite, olivine, garnet, pyrochlores, and olivine structures.

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Kaur, Hundeep, Andrea Lakatos, Roberta Spadaccini, Ramona Vogel, Christian Hoffmann, Johanna Becker-Baldus, Olivier Ouari, Paul Tordo, Hassane Mchaourab et Clemens Glaubitz. « The ABC exporter MsbA probed by solid state NMR – challenges and opportunities ». Biological Chemistry 396, n^o 9-10 (1 septembre 2015) : 1135–49. http://dx.doi.org/10.1515/hsz-2015-0119.

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Abstract ATP binding cassette (ABC) transporters form a superfamily of integral membrane proteins involved in translocation of substrates across the membrane driven by ATP hydrolysis. Despite available crystal structures and extensive biochemical data, many open questions regarding their transport mechanisms remain. Therefore, there is a need to explore spectroscopic techniques such as solid state NMR in order to bridge the gap between structural and mechanistic data. In this study, we investigate the feasibility of using Escherichia coli MsbA as a model ABC transporter for solid state NMR studies. We show that optimised solubilisation and reconstitution procedures enable preparing stable and homogenous protein samples. Depending on the duration of solubilisation, MsbA can be obtained in either an apo- or in a native lipid A bound form. Building onto these optimisations, the first promising MAS-NMR spectra with narrow lines have been recorded. However, further sensitivity improvements are required so that complex NMR experiments can be recorded within a reasonable amount of time. We therefore demonstrate the usability of paramagnetic doping for rapid data acquisition and explore dynamic nuclear polarisation as a method for general signal enhancement. Our results demonstrate that solid state NMR provides an opportunity to address important biological questions related to complex mechanisms of ABC transporters.

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Geng, Fushan, Bei Hu, Chao Li, Chong Zhao, Olivier Lafon, Julien Trébosc, Jean-Paul Amoureux, Ming Shen et Bingwen Hu. « Anionic redox reactions and structural degradation in a cation-disordered rock-salt Li1.2Ti0.4Mn0.4O2 cathode material revealed by solid-state NMR and EPR ». Journal of Materials Chemistry A 8, n^o 32 (2020) : 16515–26. http://dx.doi.org/10.1039/d0ta03358h.

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The cation-disordered rock-salt Li_1.2Ti_0.4Mn_0.4O₂ is studied by solid-state NMR and electron paramagnetic resonance (EPR) spectroscopy during the first cycle. The anionic redox and structural degradation mechanism are discussed.

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Shaibat, Medhat A., Leah B. Casabianca, Nalinda P. Wickramasinghe, Stephen Guggenheim, Angel C. de Dios et Yoshitaka Ishii. « Characterization of Polymorphs and Solid-State Reactions for Paramagnetic Systems by13C Solid-State NMR and ab Initio Calculations ». Journal of the American Chemical Society 129, n^o 36 (septembre 2007) : 10968–69. http://dx.doi.org/10.1021/ja0703980.

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Georgakopoulos, Andreas. « Aspects of solid state 13C CPMAS NMR spectroscopy in coals from the Balkan peninsula ». Journal of the Serbian Chemical Society 68, n^o 8-9 (2003) : 599–606. http://dx.doi.org/10.2298/jsc0309599g.

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The cross-polarized magic-angle-spinning NMR (CPMAS-NMR) technique was used in this work to assess the carbon distribution in coals of different rank (peat, lignite, xylite, sub-bituminous coal) from important deposits in Greece and Bulgaria. The technique is assumed to be only semiquantitative due to a number of interferences, such as spinning side bands (SSB) in the spectra, paramagnetic species in the samples, and low or remote protonation of aromatic carbons. The Bulgarian sub-bituminous coal shows the greatest amounts of aromatic structures. The lignite sample from the Drama basin Northern Greece, is relatively unaltered and largely unlettered, and shows the greatest amounts of aliphatic groups. The 13C-NMR spectra of Pliocene lignites from endemic areas in Serbia and Montenegro and Bosnia, taken from published papers, show significantly more intense resonance's for methoxyl phenolic, and polysaccharide moieties compared to the Drama lignite NMR spectrum. Xylite reveals high contents of carbohydrates.

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Schultz, Madeleine, Philipp-Nikolaus Plessow, Frank Rominger et Laura Weigel. « Structure, magnetism and colour in simple bis(phosphine)nickel(II) dihalide complexes : an experimental and theoretical investigation ». Acta Crystallographica Section C Crystal Structure Communications 69, n^o 12 (30 novembre 2013) : 1437–47. http://dx.doi.org/10.1107/s0108270113030692.

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The complex [1,2-bis(di-tert-butylphosphanyl)ethane-κ2P,P′]diiodidonickel(II), [NiI2(C18H40P2] or (dtbpe-κ2P)NiI2, [dtbpe is 1,2-bis(di-tert-butylphosphanyl)ethane], is bright blue–green in the solid state and in solution, but, contrary to the structure predicted for a blue or green nickel(II) bis(phosphine) complex, it is found to be close to square planar in the solid state. The solution structure is deduced to be similar, because the optical spectra measured in solution and in the solid state contain similar absorptions. In solution at room temperature, no31P{1H} NMR resonance is observed, but the very small solid-state magnetic moment at temperatures down to 4 K indicates that the weak paramagnetism of this nickel(II) complex can be ascribed to temperature independent paramagnetism, and that the complex has no unpaired electrons. The red [1,2-bis(di-tert-butylphosphanyl)ethane-κ2P,P′]dichloridonickel(II), [NiCl2(C18H40P2] or (dtbpe-κ2P)NiCl2, is very close to square planar and very weakly paramagnetic in the solid state and in solution, while the maroon [1,2-bis(di-tert-butylphosphanyl)ethane-κ2P,P′]dibromidonickel(II), [NiBr2(C18H40P2] or (dtbpe-κ2P)NiBr2, is isostructural with the diiodide in the solid state, and displays paramagnetism intermediate between that of the dichloride and the diiodide in the solid state and in solution. Density functional calculations demonstrate that distortion from an ideal square plane for these complexes occurs on a flat potential energy surface. The calculations reproduce the observed structures and colours, and explain the trends observed for these and similar complexes. Although theoretical investigation identified magnetic-dipole-allowed excitations that are characteristic for temperature-independent paramagnetism (TIP), theory predicts the molecules to be diamagnetic.

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Jensen, Nicholai Daugaard, Claude Forano, Suraj Shiv Charan Pushparaj, Yusuke Nishiyama, Belayneh Bekele et Ulla Gro Nielsen. « The distribution of reactive Ni2+ in 2D Mg2−xNixAl-LDH nanohybrid materials determined by solid state 27Al MAS NMR spectroscopy ». Physical Chemistry Chemical Physics 20, n^o 39 (2018) : 25335–42. http://dx.doi.org/10.1039/c8cp05243c.

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He, Lichun, Benjamin Bardiaux, Mumdooh Ahmed, Johannes Spehr, Renate König, Heinrich Lünsdorf, Ulfert Rand, Thorsten Lührs et Christiane Ritter. « Structure determination of helical filaments by solid-state NMR spectroscopy ». Proceedings of the National Academy of Sciences 113, n^o 3 (5 janvier 2016) : E272—E281. http://dx.doi.org/10.1073/pnas.1513119113.

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The controlled formation of filamentous protein complexes plays a crucial role in many biological systems and represents an emerging paradigm in signal transduction. The mitochondrial antiviral signaling protein (MAVS) is a central signal transduction hub in innate immunity that is activated by a receptor-induced conversion into helical superstructures (filaments) assembled from its globular caspase activation and recruitment domain. Solid-state NMR (ssNMR) spectroscopy has become one of the most powerful techniques for atomic resolution structures of protein fibrils. However, for helical filaments, the determination of the correct symmetry parameters has remained a significant hurdle for any structural technique and could thus far not be precisely derived from ssNMR data. Here, we solved the atomic resolution structure of helical MAVSCARD filaments exclusively from ssNMR data. We present a generally applicable approach that systematically explores the helical symmetry space by efficient modeling of the helical structure restrained by interprotomer ssNMR distance restraints. Together with classical automated NMR structure calculation, this allowed us to faithfully determine the symmetry that defines the entire assembly. To validate our structure, we probed the protomer arrangement by solvent paramagnetic resonance enhancement, analysis of chemical shift differences relative to the solution NMR structure of the monomer, and mutagenesis. We provide detailed information on the atomic contacts that determine filament stability and describe mechanistic details on the formation of signaling-competent MAVS filaments from inactive monomers.

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Carr, Christopher M., et Walter V. Gerasimowicz. « A Carbon-13 CPMAS Solid State NMR Spectroscopic Study of Wool : Effects of Heat and Chrome Mordanting ». Textile Research Journal 58, n^o 7 (juillet 1988) : 418–21. http://dx.doi.org/10.1177/004051758805800708.

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Carbon-13 CPMAS solid state NMR spectroscopy has been used to investigate the effect of heat on wool. Increases in the unsaturation of the keratin are observed at 225°C. The technique has also been used to show that paramagnetic chromium appears to interact uniformly throughout the bulk of the wool fiber when the fiber is treated with a dichromate solution.

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Ganapathy, S., P. R. Rajamohanan, P. Ganguly, T. N. Venkatraman et Anil Kumar. « Two-Dimensional Solid State NMR and Separation of7Li Quadrupolar Interactions in Paramagnetic Compounds ». Journal of Physical Chemistry A 104, n^o 10 (mars 2000) : 2007–12. http://dx.doi.org/10.1021/jp9822384.

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Linser, Rasmus, Veniamin Chevelkov, Anne Diehl et Bernd Reif. « Sensitivity enhancement using paramagnetic relaxation in MAS solid-state NMR of perdeuterated proteins ». Journal of Magnetic Resonance 189, n^o 2 (décembre 2007) : 209–16. http://dx.doi.org/10.1016/j.jmr.2007.09.007.

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