Cross-β Spine Architecture of Fibrils Formed by the Amyloidogenic Segment NFGSVQFV of Medin from Solid-State NMR and X-ray Fiber Diffraction Measurements†

Hydrophobic treatment is one of the most important interventions usually carried out for the conservation of stone artefacts and monuments. The study here reported aims to answer a general question about how two polymers confer different protective performance. Two fluorinated-based polymer formulates applied on samples of Cusa’s stone confer a different level of water repellence and water vapour permeability. The observed protection action is here explained on the basis of chemico-physical interactions. The distribution of the polymer in the pore network was investigated using scanning electron microscopy and X-ray microscopy. The interactions between the stone substrate and the protective agents were investigated by means of solid state NMR spectroscopy. The ss-NMR findings reveal no significant changes in the chemical neighbourhood of the observed nuclei of each protective agent when applied onto the stone surface and provide information on the changes in the organization and dynamics of the studied systems, as well as on the mobility of polymer chains. This allowed us to explain the different macroscopic behaviours provided by each protective agent to the stone substrate.

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Synthesis, characterization and modeling of self-assembled porphyrin nanorods

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619501451 ◽

2019 ◽

Vol 23 (11n12) ◽

pp. 1346-1354 ◽

Cited By ~ 1

Author(s):

Danielle Laurencin ◽

Pascal G. Yot ◽

Christel Gervais ◽

Yannick Guari ◽

Sébastien Clément ◽

...

Keyword(s):

Solid State ◽

Nmr Spectroscopy ◽

Dft Calculations ◽

Powder Diffraction ◽

Solid State Nmr ◽

Molecular Level ◽

Ion Association ◽

Free Base ◽

X Ray ◽

Solid State Nmr Spectroscopy

Porphyrin nanorods were prepared by ion-association between free-base meso 5,10,15,20-tetrakis-(4-[Formula: see text]-methylpyridinium)porphyrin cations and tetraphenylborate anions. The nanorods have variable lengths (up to a few micrometers long) and diameters ([Formula: see text]50–500 nm). Their structure at the molecular level was elucidated by combining multinuclear solid state NMR spectroscopy, synchrotron X-ray powder diffraction and DFT calculations.

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Characterization of some mesogenic alkyl 1-thioglycosides

Canadian Journal of Chemistry ◽

10.1139/v02-157 ◽

2002 ◽

Vol 80 (8) ◽

pp. 1162-1165 ◽

Cited By ~ 2

Author(s):

B Henrissat ◽

G K Hamer ◽

M G Taylor ◽

R H Marchessault

Keyword(s):

Phase Transition ◽

Liquid Crystal ◽

Solid State ◽

Solid State Nmr ◽

Liquid Crystalline ◽

Liquid Crystal Phase ◽

X Ray Diffraction ◽

X Ray ◽

Liquid Crystalline Phases

A series of dodecyl 1-thio-β-D-glycosides has been synthesized and characterized (DSC, NMR, CP MAS, X-ray diffraction) as possible new marking materials with liquid-crystalline properties. These compounds undergo solid to liquid crystal phase transitions at various temperatures, which depend on the nature of the carbohydrate part of the structure. Their liquid-crystalline phases show extreme shear thinning behaviour.Key words: liquid crystal, powder X-ray diffraction, phase transition, thioglycoside, solid-state NMR, marking material

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