Differential scanning calorimetry and deuterium NMR studies of the phase behavior of gramicidin-phosphatidylcholine mixtures

Biochemistry ◽  
1988 ◽  
Vol 27 (6) ◽  
pp. 2024-2032 ◽  
Author(s):  
Michael R. Morrow ◽  
James H. Davis
Keyword(s):  
Differential Scanning Calorimetry ◽  
Phase Behavior ◽  
Deuterium Nmr ◽  
Scanning Calorimetry ◽  
Nmr Studies

1H nuclear magnetic resonance, differential scanning calorimetry, and electrical conductivity studies on the phase transitions of pentylammonium chloride and the cationic self-diffusion in its rotator phase

1988 ◽  
Vol 66 (8) ◽  
pp. 1961-1969 ◽  
Author(s):  
Shigehiko Iwai ◽  
Ryuichi Ikeda ◽  
Daiyu Nakamura
Keyword(s):  
Phase Transition ◽  
Electrical Conductivity ◽  
Differential Scanning Calorimetry ◽  
Room Temperature ◽  
Stable Phase ◽  
Scanning Calorimetry ◽  
Nmr Studies ◽  
Self Diffusion ◽  
H Nmr ◽  
Rotator Phase

Measurements of 1H nmr, differential thermal analysis, and differential scanning calorimetry have revealed that solid pentylammonium chloride, cooled rapidly from room temperature, forms a mixture of the stable and metastable low-temperature phases below the phase transition temperature, Ttr (238 K). The sample annealed just below Ttr for 3 h was shown to consist of a single stable phase down to about 100 K, indicating the existence of a time-consuming phase transition taking place successively just below the normal transition. In the rotator phase obtainable above Ttr (257 K), 1H nmr studies proved the presence of axial rotation of the whole cation about the long axis, similar to n-paraffins in their rotator phase. Above room temperature, the onset of the translational self-diffusion of the cations within 2D planes in the layer structure of the rotator phase was detected by measuring the temperature dependence of electrical conductivity as well as 1H T1 and T1p. 2D self-diffusion constants and diffusional correlation times evaluated from the electrical conductivity observed between room and the melting temperatures indicate that the 2D cationic diffusion near the melting point is as fast as 3D self-diffusion in usual plastic crystals. Cationic motions in the two different rotator phases α and α′ are compared.

Solid phase behavior of mixture systems based on tripalmitoyl glycerol and monounsaturated triacylglycerols forming a molecular compound

2022 ◽  
Author(s):  
Jorge Macridachis ◽  
Laura Bayés-García ◽  
Teresa Calvet
Keyword(s):  
Differential Scanning Calorimetry ◽  
Phase Behavior ◽  
Solid Phase ◽  
Molecular Compound ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Mixing Behavior

Differential scanning calorimetry and X-ray diffraction were used to investigate the mixing behavior of triacylglycerol (TAG) mixtures of PPP/PPO (tripalmitoyl glycerol/1,2-dipalmitoyl-3-oleoyl-rac-glycerol) and PPP/MCPOP/PPO (being MCPOP/PPO the equimolecular blend of 1,3-dipalmitoyl-2-oleoyl-glycerol...

scholarly journals Collective orientational order and phase behavior of a discotic liquid crystal under nanoscale confinement

2019 ◽  
Vol 1 (3) ◽  
pp. 1104-1116 ◽  
Author(s):  
Arda Yildirim ◽  
Kathrin Sentker ◽  
Glen Jacob Smales ◽  
Brian Richard Pauw ◽  
Patrick Huber ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Phase Behavior ◽  
Dielectric Spectroscopy ◽  
Orientational Order ◽  
Scanning Calorimetry ◽  
Discotic Liquid Crystal ◽  
Molecular Ordering

The phase behavior and molecular ordering of hexakishexyloxy triphenylene (HAT6) DLCs under cylindrical nanoconfinement, for nanopore diameters ranging from 161 nm down to 12 nm, are studied utilizing differential scanning calorimetry (DSC) and dielectric spectroscopy (DS).

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