Revealing complex formation in acetone–n-alkane mixtures by MAS PFG NMR diffusion measurement in nanoporous hosts

2008 ◽  
Vol 10 (28) ◽  
pp. 4165 ◽  
Author(s):  
Moises Fernandez ◽  
André Pampel ◽  
Ryoji Takahashi ◽  
Satoshi Sato ◽  
Dieter Freude ◽  
...  
Keyword(s):  
Complex Formation ◽  
Diffusion Measurement ◽  
Nmr Diffusion ◽  
Pfg Nmr

Diffusion NMR and bicelle morphology

2011 ◽  
Vol 89 (9) ◽  
pp. 1021-1035 ◽  
Author(s):  
Peter M. Macdonald ◽  
Ronald Soong
Keyword(s):  
Lateral Diffusion ◽  
Diffusion Method ◽  
Nmr Studies ◽  
Diffusion Nmr ◽  
Magnetically Aligned Bicelles ◽  
Diffusion Studies ◽  
Membrane Bound ◽  
Nmr Diffusion ◽  
Pfg Nmr ◽  
Magnetically Aligned

This minireview focuses on diffusion NMR studies in bicelles. Following a discourse on diffusion fundamentals, and a comparative overview of fluorescence and NMR-based techniques for measuring diffusion, the pulsed field gradient (PFG) NMR diffusion method is introduced, emphasizing its specific advantages and limitations when applied to diffusion measurements in macroscopically oriented lamellar systems such as magnetically aligned bicelles. The utility of PFG NMR diffusion measurements in bicellar model membrane systems for examining lateral diffusion of membrane-bound molecular species is demonstrated, along with certain features of lateral diffusion that such studies illuminate. Further, those aspects of bicelle morphology that have been resolved using PFG NMR diffusion studies of various molecular weight soluble polymeric species are reviewed. The discussion concludes with an outline of future prospects for diffusion NMR studies in bicelles.

Li ion Conduction in Cross-Linked Peo-LiCF3SO3 Complex

1988 ◽  
Vol 135 ◽  
Author(s):  
Jun Tsuchiya
Keyword(s):  
Diffusion Coefficient ◽  
Room Temperature ◽  
Transport Number ◽  
Diffusion Measurement ◽  
Poly Ethylene Oxide ◽  
Li Ion ◽  
Poly Ethylene ◽  
Pfg Nmr ◽  
And Diffusion ◽  
Ion Transport Number

AbstractIonic migration of cross-linked amorphous Poly (Ethylene Oxide)-LiCF3SO3was investigated by measuring ionic conductivity and diffusion coefficient. Pulsed-Field-Gradient NMR (PFG-NMR) was used for the diffusion measurement. The measurements were carried out at a temperature region between room temperature and 120°C. The PFG-NMR mea-surement shows the two modes of migration of both cation(Li) and anion (CF3 SO3-) for specimens containing plasticizer (CH30(CHeiH20)gH3C). The two modes of migration for anion are present for specimens without the plasticizer. Li+ transport number is found to be less than 0.1 for specimens without the plasticizer. Plasticizer is found to increase the Li+ ion transport number.

Exploring the hierarchy of transport phenomena in hierarchical pore systems by NMR diffusion measurement

2012 ◽  
Vol 164 ◽  
pp. 273-279 ◽  
Author(s):  
Dirk Mehlhorn ◽  
Rustem Valiullin ◽  
Jörg Kärger ◽  
Kanghee Cho ◽  
Ryong Ryoo
Keyword(s):  
Transport Phenomena ◽  
Diffusion Measurement ◽  
Nmr Diffusion ◽  
Hierarchical Pore

scholarly journals Comment on “Boosted molecular mobility during common chemical reactions”

Science ◽  
2021 ◽  
Vol 371 (6526) ◽  
pp. eabe8322
Author(s):  
Jan-Philipp Günther ◽  
Lucy L. Fillbrook ◽  
Thomas S. C. MacDonald ◽  
Günter Majer ◽  
William S. Price ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Reactions ◽  
Molecular Mobility ◽  
Diffusion Coefficients ◽  
Diffusion Measurement ◽  
Nmr Diffusion ◽  
Signal Intensities ◽  
Nuclear Magnetic

The apparent “boosted mobility” observed by Wang et al. (Reports, 31 July 2020, p. 537) is the result of a known artifact. When signal intensities are changing during a nuclear magnetic resonance (NMR) diffusion measurement for reasons other than diffusion, the use of monotonically increasing gradient amplitudes produces erroneous diffusion coefficients. We show that no boosted molecular mobility is observed when shuffled gradient amplitudes are applied.

scholarly journals Intermolecular Hydrogen Bonding of Steroid Compounds: PFG NMR Diffusion Study, Cold-Spray Ionization (CSI)-MS and X-Ray Analysis

2005 ◽  
Vol 53 (7) ◽  
pp. 792-795 ◽  
Author(s):  
Kazuaki Shikii ◽  
Hiroko Seki ◽  
Shigeru Sakamoto ◽  
Yoshihisa Sei ◽  
Hiroaki Utsumi ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Cold Spray ◽  
Intermolecular Hydrogen Bonding ◽  
Diffusion Study ◽  
X Ray ◽  
Nmr Diffusion ◽  
Pfg Nmr

PFG NMR diffusion measurements of CH4 and CO2 through large ZSM-58-crystals

2013 ◽  
Vol 182 ◽  
pp. 25-31 ◽  
Author(s):  
Bjørn-Tore Lønstad Bleken ◽  
Karl Petter Lillerud ◽  
Tobias Splith ◽  
Anne-Kirstin Pusch ◽  
Frank Stallmach
Keyword(s):  
Nmr Diffusion ◽  
Pfg Nmr

Nafion® Membranes: Molecular Diffusion, Proton Conductivity and Proton Conduction Mechanism

1992 ◽  
Vol 293 ◽  
Author(s):  
Klaus-Dieter Kreuer ◽  
Thomas Dippel ◽  
Wolfgang Meyer ◽  
Joachim Maier
Keyword(s):  
Water Content ◽  
Proton Conductivity ◽  
Molecular Diffusion ◽  
Local Environment ◽  
Bulk Water ◽  
Exponential Factor ◽  
Nmr Diffusion ◽  
The One ◽  
Low Degrees ◽  
Pfg Nmr

AbstractH-PFG-NMR diffusion and proton conductivity data for NAFION® 117 is presented as a function of temperature and water content. From this, H2O diffusion on a molecular scale is concluded to be similar to the one in bulk water. But “geometrical” restrictions of diffusion lead to a decreasing pre-exponential factor, i.e. decreasing macroscopic diffusion coefficient with decreasing water content. It is shown that proton conductivity is correlated with water diffusion for low degrees of hydration (vehicle mechanism). With increasing hydration there is an increasing contribution from “structure diffusion” culminating in an amplification factor of A = 2.5 for fully hydrated protonic NAFION® 117 at room temperature. The bonding of water in NAFION® as well as the local environment (hydration) of the acidic proton are concluded to be similar as in acidic aqueous solutions.

scholarly journals Comment on “Boosted Molecular Mobility During Common Chemical Reactions"

2020 ◽  
Author(s):  
Jan-Philipp Günther ◽  
Lucy Fillbrook ◽  
Thomas MacDonald ◽  
Günter Majer ◽  
William S. Price ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Diffusion Coefficient ◽  
Magnetic Resonance ◽  
Chemical Reactions ◽  
Molecular Mobility ◽  
Diffusion Measurement ◽  
Nmr Diffusion ◽  
Signal Intensities ◽  
Nuclear Magnetic

The apparent “boosted mobility” observed by nuclear magnetic resonance (NMR) diffusion measurements is the result of a known artefact. When signal intensities are changing during an NMR diffusion measurement for reasons other than diffusion, the use of monotonically increasing gradient amplitudes produces erroneous diffusion coefficient values. We show that no boosted molecular mobility is observed when shuffled gradient amplitudes are applied.

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