Liquid crystal , studies

Zennyoji M, Takanishi Y, Ishikawa K, Thisayukta J, Watanahe J, Takezoe H (2001) Molecular chirality due to twisted conformation in a bent-shaped liquid crystal studied by polarized FT-IR spectroscopy. Mol Cryst Liq Cryst 366 2545-2553... 

N. Boden, Y. K. Levine, D. Lightowlers, and R. T. Squires, "NMR dipolar echoes in liquid crystals," Chem. Phys. Letters 31, 511 (1975) "Internal molecular disorder in the nematic and smectic phases of thermotropic liquid crystals studied by NMR SPDE experiments," ibid 34, 63-68 (1975). 

Polarization or polarized microscopy is an irreplaceable tool for studying materials with refractory activity. In the case of liquid crystal study, two states of material, crystal and liquid crystal, have birefringent activity. In our studies, we have found microscopy to be an invaluable tool in examining the light activity of liquid crystals in animal tissue. 

Fig. 2 Chemical structures of liquid crystals studied for the preparation of LC physical gels...

A. C. Tracey, P. Diehl Lyotropic Liquid Crystals 18 figures, 3 tables. IV, 85 pages. 1975 Contents Nuclear Magnetic Resonance Studies in Lyotropic Liquid Crystals Introduction.— Studies of Lyotropic Liquid Crystals. — Studies of Molecular and Ionic Species Dissolved in the Nematic Phase of Lyotropic Liquid Crystals. 

The mathematics of spherical harmonics is an accepted tool in many scientific disciplines and is treated in several classic texts. In 1939 the method was applied to orientation in materials by Hermans and Platzek, who used just P2), which is often referred to as the Hermans orientation function. Spherical harmonics were applied to liquid crystals in the theoretical work of Maier and Saupe, who again emphasized only (Pj)- However, they called it the order parameter and designated it S, setting a nomenclature which is now standard in liquid crystal studies. 

The reaction of D-gludtol with 4-isobutylbenzaldehyde m addic methanol, which furnishes mainly the l,3 2,4-di-0-acetal, has been discussed. A novd method for the synthesis of substituted ben idene acetals involved treatment of a diol mth the appropriate benzalddiyde in the presence of TPP and MBS which are thought to form a reactive qredes 20 an exanq>le is shown in Scheme 4." The 4,6-0-(4-cyanobenz3iidene) acetals 21, required for liquid crystal studies, have been prqiared by exposure of the corresponding 4,6-diols to cyanobenzalddiyde dimeth acetal and tohienesulfonic add in DMF. ... 

DSC (heat flow versus temperature curve) is particularly well suited to the detection and study of liquid crystals. Studies of transition temperatures and enthalpies, range of stability, and states of reversion from one form to another are all possible. 

Figure 12. Polymeric liquid crystals studied as erasable media.

Measurement of variation of spectrum with temperature. Liquid-crystal study. 

Zhao Tongyang, and Wang Xiaogong. Phase behavior of lyotropic rigid-chain polymer liquid crystal studied by dissipative particle dynamics. J. Chem. Phys. 135 (2011) 244901. 

Liquid crystal study degree of alignment. Dynamic nuclear polarization study of Li complex. 

D. Goldfarh, 1. Belsky, Z. Luz, and H. Zimmermaim, Axial-hiaxial phase transition in discotic liquid crystals studied hy heuterium NMR, J. Chem. Phys. 79 6203-6210 (1983). 

R. Y. Dong and C. R. Morcombe, Rotational dynamics of a discotic liquid crystal studied by deuteron spin relaxation, Liq. Cryst. 27 897-900 (2000). 

S. V. Dvinskikh, I. Furo, H. Zrmmermann, and A. Maliniak, Anisotropic self-diffusion in thermotropic liquid crystals studied by H and pulsed-field-gradient spin-echo NMR, Phys. Rev. E 65, 061701-1/9 (2002). 

Rayleigh wing scattering is due to the orientational fluctuations of the anisotropic molecules. For typical liquids these orientational fluctuations are characteristic of the individual molecules movements and occur in a very short time scale (< 10 s). Consequently, the spectrum is quite broad. In liquid crystals studies of individual molecular orientation dynamics have shown that the relaxation time scale is on the order of picoseconds and thus the Rayleigh wing spectrum for liquid crystals is also quite broad. 

On treatment with a non-enolizable aldehyde and sodium hydride, rruns-related a-hydroxyepoxides were converted to acetals. The reaction is thought to proceed by way of a hemiacetal salt, as illustrated in Scheme 2. L-Galactono-1,4-lactone, a by-product of the sugar industry, furnished a diastereomeric mixture of 5,6-alkylidene acetals 18 in >60% yield on microwave irradiation in the presence of long-chain aldehydes and montmorillonite KSF as catalyst, and 4,6-O-alkylidene derivatives 19 of D-glucose have been prepared by use of long-chain aldehydes and catalytic pyridinium />-toluenesulfonate in benzene under azeotropic removal of water. Compounds 18 and 19 were of interest in liquid crystal studies. 

Shen, X., et al. Orientational ordering tind dynamics in the colmnnar phase of a discotic liquid crystal studied by deuteron NMR spectroscopy. J. Chem. Phys. 108(10), 4324-4332 (1998). doi 10.1063/1.475833... 

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