The influence of N-acyl chain length on the thermotropic phase behaviour of N-acylphosphatidylethanolamines of natural origin was studied by DSC, 3~P-NMR and IR-FT spectroscopy. The obtained data were also compared with the known behaviour of N-acyl derivates of dipalmitoylphosphatidylethanolamine.
The influence of chain length on the hydrodynamic behaviour of amylose
β Scribed by Philippe Roger; Paul Colonna
- Publisher
- Elsevier Science
- Year
- 1992
- Tongue
- English
- Weight
- 708 KB
- Volume
- 227
- Category
- Article
- ISSN
- 0008-6215
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β¦ Synopsis
Dilute aqueous solutions of amylose (< 1.5 mg/mL) have been studied by static and dynamic light-scattering techniques. The samples used were monodisperse fractions which covered molecular weights in the range 2 x lo4 -1 x 106. The hydrodynamic radii (RH) were computed from the translational diffusion coefficient at infinite dilution. The characteristic exponents for the dependence of the molecular weight on the dimensions of the polymer chain in good solvents, determined as vo for R. values and vu for R, values, respectively, were close to the value predicted for a 19 solvent in 0.1~ KC1 (vu 0.47, vo 0.51) and for a good solvent in 0.1~ KOH (vu 0.57, vo 0.67). The ratio c = R,/RG is discussed, as is the stiffness of the polymer in those solvents on the basis of the persistence length. * Dedicated to Professor David Manners.
π SIMILAR VOLUMES
## Abstract Diβ__n__βalkyl substituted polyfluorenes with alkyl chain lengths of 6, 7, 8, 9, and 10 carbon atoms (PF6, PF7, PF8, PF9, and PF10) are studied in dilute solution in MCH using optical spectroscopy. Betaβphase is formed upon cooling in solutions (βΌ 7βΒ΅g mL^β1^) of PF7, PF8, and PF9 only,