Spectroscopic studies of trans -l,6-diphenyl-1,3,5-hexatriene in ordered liquid crystal solutions

1973 ◽  
Vol 335 (1602) ◽  
pp. 387-405 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Liquid Crystal ◽  
Fluorescence Polarization ◽  
Polarized Light ◽  
Spectroscopic Studies ◽  
Main Axis ◽  
Electronic Transitions ◽  
Absorption Data ◽  
Fluorescence Methods ◽  
Crystal Mixture

A detailed study has been made of the absorption spectrum of all trans-1,6 diphenyl-1,3,5- hexatriene dissolved in a nematic liquid crystal mixture (1.95:1 cholesteryl chloride and cholestryl laurate (by mass)) using polarized light. Apart from two transitions with moments directed along the molecular axis a transition between these two perpendicular to the main axis has been discovered. This is attributed to a 1A -1G transition, predicted by theory. The application of ordered system s to the resolution of transitions in the absorption spectrum has been checked by a comparison with fluorescence polarization methods. A theory has been developed for the treatment of absorption data in ordered media and the effects of distribution of molecular orientations examined. The technique presented is found to be better in several respects than fluorescence methods for identification of electronic transitions.

scholarly journals Design and Realization of a Compact Efficient Beam Combiner, Based on Liquid Crystal Pancharatnam–Berry Phase Gratings

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 220
Author(s):  
Boxuan Gao ◽  
Jeroen Beeckman ◽  
Kristiaan Neyts
Keyword(s):  
Liquid Crystal ◽  
Berry Phase ◽  
Polarized Light ◽  
Laser Beams ◽  
Circularly Polarized Light ◽  
Circularly Polarized ◽  
Beam Combiner ◽  
High Diffraction Efficiency ◽  
High Diffraction ◽  
Crystal Mixture

We demonstrate a laser beam combiner based on four photo-patterned Pancharatnam–Berry (PB) phase gratings, which is compact and has high diffraction efficiency for incident circularly polarized light. The nematic liquid crystal mixture E7 is used as anisotropic material, and the thickness of the layer is controlled by spacers. The beam combiner can bring two parallel laser beams closer to each other while remaining parallel. This work shows the potential to realize components based on flat optical LC devices.

Self-Regulation of Infrared Using a Liquid Crystal Mixture Doped with Push–Pull Azobenzene for Energy-Saving Smart Windows

2021 ◽  
Vol 13 (4) ◽  
pp. 5028-5033
Author(s):  
Seung-Won Oh ◽  
Seung-Min Nam ◽  
Sang-Hyeok Kim ◽  
Tae-Hoon Yoon ◽  
Wook Sung Kim
Keyword(s):  
Liquid Crystal ◽  
Energy Saving ◽  
Self Regulation ◽  
Smart Windows ◽  
Crystal Mixture

Electro-optic effects in a ferroelectric liquid crystal mixture

1989 ◽  
Vol 92 (1) ◽  
pp. 353-354
Author(s):  
D. K. Rout ◽  
R. N. P. Choudhary ◽  
G. D. Nigam
Keyword(s):  
Liquid Crystal ◽  
Ferroelectric Liquid Crystal ◽  
Electro Optic ◽  
Crystal Mixture

Lamellar Lyotropic Liquid Crystal Phases as a Carrier for Skin Delivery of Morus alba Stem Extract

2021 ◽  
Vol 901 ◽  
pp. 67-72
Author(s):  
Chein Yhirayha ◽  
Sakchai Wittaya-Areekul ◽  
Tasana Pitaksuteepong
Keyword(s):  
Liquid Crystal ◽  
Biological Activities ◽  
Polarized Light ◽  
Water Extract ◽  
Skin Penetration ◽  
Morus Alba ◽  
Lyotropic Liquid Crystal ◽  
Mixed Surfactant ◽  
Skin Delivery ◽  
Stem Extract

Morus alba stem extract possesses several biological activities. However, skin delivery of the extract is limited by the stratum corneum. In this study, lamellar lyotropic liquid crystal (LLC) was investigated for the potential application in the skin delivery of M. alba stem extract. The four formulations were developed and incorporated with M. alba stem extract at 3% w/w. These formulations were stored at room temperature in light-protected containers for 3 months. The optical pattern under polarized light microscope, viscosity and remaining of the extract were determined. The skin penetration enhancing property of the formulations was investigated using excised porcine ear skin model. The results showed that all formulations remained stable after 3-month storage. The two formulations exhibiting good penetration enhancing properties were F3 consisting of PEG-7 glyceryl cocoate/n-Dodecane/Water/extract (55.29/19.40/22.31/3.00 %w/w) and F4 consisting of mixed Surfactant/n-Dodecane/Water/extract (48.50/4.85/43.65/3.00 %w/w). The mixed surfactant composed of PEG-7 glyceryl cocoate/PEG-40 hydrogenated castor oil/Glyceryl oleate (40/33.24/26.76 %w/w). It can be concluded that the lamellar LLC formulations developed in this study can be used as a carrier for delivering of M. alba stem extract. The components of the formulations which play important roles are the oil and the surfactant.

A practical liquid crystal mixture for IR applications

2003 ◽  
Vol 30 (5) ◽  
pp. 623-626 ◽  
Author(s):  
Chibing Tan ◽  
B. M. Fung
Keyword(s):  
Liquid Crystal ◽  
Crystal Mixture

scholarly journals Kinetochore-driven outgrowth of microtubules is a central contributor to kinetochore fiber maturation in crane-fly spermatocytes

2014 ◽  
Vol 25 (9) ◽  
pp. 1437-1445 ◽  
Author(s):  
James R. LaFountain ◽  
Rudolf Oldenbourg
Keyword(s):  
Liquid Crystal ◽  
Life Histories ◽  
Polarized Light ◽  
Fiber Formation ◽  
Image Brightness ◽  
Early Stages ◽  
Anaphase Onset ◽  
Bipolar Spindles ◽  
Polarized Light Imaging

We use liquid crystal polarized light imaging to record the life histories of single kinetochore (K-) fibers in living crane-fly spermatocytes, from their origins as nascent K-fibers in early prometaphase to their fully matured form at metaphase, just before anaphase onset. Increased image brightness due to increased retardance reveals where microtubules are added during K-fiber formation. Analysis of experimentally generated bipolar spindles with only one centrosome, as well as of regular, bicentrosomal spindles, reveals that microtubule addition occurs at the kinetochore-proximal ends of K-fibers, and added polymer expands poleward, giving rise to the robust K-fibers of metaphase cells. These results are not compatible with a model for K-fiber formation in which microtubules are added to nascent fibers solely by repetitive “search and capture” of centrosomal microtubule plus ends. Our interpretation is that capture of centrosomal microtubules—when deployed—is limited to early stages in establishment of nascent K-fibers, which then mature through kinetochore-driven outgrowth. When kinetochore capture of centrosomal microtubules is not used, the polar ends of K-fibers grow outward from their kinetochores and usually converge to make a centrosome-free pole.

Sign in / Sign up

Export Citation Format

Share Document