Deuterium NMR Studies of the Orientational Order Parameter of Poly(γ-benzyl L-glutamate)s in the Lyotropic Liquid Crystalline State

1987 ◽  
Vol 19 (6) ◽  
pp. 777-780 ◽  
Author(s):  
Toshimasa Yamazaki ◽  
Akihiro Abe
Keyword(s):  
Order Parameter ◽  
Crystalline State ◽  
Liquid Crystalline ◽  
Orientational Order ◽  
Deuterium Nmr ◽  
Orientational Order Parameter ◽  
Nmr Studies ◽  
Liquid Crystalline State

Thermal Behaviour of Lymphocyte Membrane: ESR Investigation

1990 ◽  
Vol 45 (9-10) ◽  
pp. 1060-1062 ◽  
Author(s):  
S. Mazzuca ◽  
L. Sportelli
Keyword(s):  
Staphylococcus Aureus ◽  
Plasma Membrane ◽  
Order Parameter ◽  
Crystalline State ◽  
Liquid Crystalline ◽  
Human Peripheral Blood ◽  
Electron Spin Resonance Spectroscopy ◽  
Resonance Spectroscopy ◽  
Liquid Crystalline State ◽  
Spin Resonance

Abstract The order parameter, S, of the plasma membrane of in toto human peripheral blood lym­ phocytes was obtained by electron spin resonance spectroscopy in the temperature range 25-41°C. This membrane is completely in the liquid crystalline state above 31 °C. In presence of the antigen ETB from Staphylococcus aureus at the concentration of 4 μ/3 × 107 cells an overall decrease of the order parameter for this membrane is observed. The decrease of 5 is followed by an upwards shift at about 35 °C of the temperature of the liquid crystalline state.

scholarly journals DNA Origami Nano-Sheets and Nano-Rods Alter the Orientational Order in a Lyotropic Chromonic Liquid Crystal

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1695
Author(s):  
Bingru Zhang ◽  
Kevin Martens ◽  
Luisa Kneer ◽  
Timon Funck ◽  
Linh Nguyen ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Order Parameter ◽  
Liquid Crystalline ◽  
Orientational Order ◽  
Dna Origami ◽  
Nano Particles ◽  
Width Ratio ◽  
Disodium Cromoglycate ◽  
Orientational Order Parameter ◽  
Nano Rods

Rod-like and sheet-like nano-particles made of desoxyribonucleic acid (DNA) fabricated by the DNA origami method (base sequence-controlled self-organized folding of DNA) are dispersed in a lyotropic chromonic liquid crystal made of an aqueous solution of disodium cromoglycate. The respective liquid crystalline nanodispersions are doped with a dichroic fluorescent dye and their orientational order parameter is studied by means of polarized fluorescence spectroscopy. The presence of the nano-particles is found to slightly reduce the orientational order parameter of the nematic mesophase. Nano-rods with a large length/width ratio tend to preserve the orientational order, while more compact stiff nano-rods and especially nano-sheets reduce the order parameter to a larger extent. In spite of the difference between the sizes of the DNA nano-particles and the rod-like columnar aggregates forming the liquid crystal, a similarity between the shapes of the former and the latter seems to be better compatible with the orientational order of the liquid crystal.

Orientational Order of α-Helical Poly (γ-Benzyl L-Glutamate) in the Lyotrao-Phiecl Ilciaqlu Idp Oclryy(yS-Tbaelnlziynle Ls-Tate and Conformation of the Pendant Side Chain

1988 ◽  
Vol 134 ◽  
Author(s):  
Akihiro Abe ◽  
Toshimasa Yamazaki
Keyword(s):  
Crystalline State ◽  
Liquid Crystalline ◽  
Orientational Order ◽  
Equilibrium Concentration ◽  
Side Chain ◽  
Side Chains ◽  
Nmr Studies ◽  
Rotational Isomeric State ◽  
System A ◽  
Acid Esters

ABSTRACTDeuterium NMR studies have been performed on variously labeled PBLG samples in the lyotroplc liquid crystalline state. The orientational orders S of the a-helical backbone were estimated from the observed quadrupolar splittings ∆v of the N-D and Cα-D bond. The values of S decrease gradually by dilution until the upper equilibrium concentration (B-point) is reached. The concentration dependence of Scrit has been compared with those derived from standard theories. The relatlve orientation of side chains with respect to the backbone was elucidated by the rotational isomeric state analysis of the ∆v/S data observed for the γ-, γ-, and ζ-methylene, and p-benzyl deuterons. The results indicate that the steric overlaps between adjacent side chains play an important role in determining the preference of conformations in the PBLG system. A similar analysis has been extended to poly(L-glutamic acid) esters carrying a homologous series of ester residues, -C(O)O(CH2)nC6D5 with n = 2 and 3. A distinct odd-even oscillation was observed for the orientation of the terminal phenyl groups with n.

Optical Study of Orientational Order Parameter in p-n-(Phenyl Benzylidene) -p-Alkyl and Alkyloxy Anilines

2011 ◽  
Vol 181-182 ◽  
pp. 75-78 ◽  
Author(s):  
B.R. Rajeswari ◽  
P. Pardhasaradhi ◽  
M. Ramakrishna Nanachara Rao ◽  
P.V. Datta Prasad ◽  
D. Madhavi Latha ◽  
...  
Keyword(s):  
Order Parameter ◽  
Liquid Crystalline ◽  
Orientational Order ◽  
Molecular Vibration ◽  
Refractive Indices ◽  
Orientational Order Parameter ◽  
Optical Study ◽  
Shaped Cell ◽  
Scaling Methods ◽  
Molecular Polarizabilities

The refractive indices measurements are carried out using a modified spectrometer connected with wedge shaped cell and also the direct measurement of birefringence,δn obtained from Newton’s rings method with an indigenous setup for the liquid crystalline compoundsp-n-(phenyl benzylidene)-p-n-alkyl and alkyloxy anilines, PBnA and PBnOA compounds. The molecular polarizabilitiy anisotropy (α||- α⊥) is calculated for these compounds from different methods such as Lippincott δ-function model, molecular vibration method, Haller’s extrapolation method and scaling methods respectively. Further, the estimation of the molecular polarizabilities αeand αoare done from the isotropic Vuks and anisotropic Neugebauer models. The order parameter directly calculated from ∆n employing the method developed by Kuczynski is compared with the order parameter estimated from the different models using molecular polarizabilities.

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