The microwave heating mechanism of N-(4-methoxybenzyliden)-4-butylaniline in liquid crystalline and isotropic phases as determined using in situ microwave irradiation NMR spectroscopy

2015 ◽  
Vol 17 (14) ◽  
pp. 9082-9089 ◽  
Author(s):  
Yugo Tasei ◽  
Fumikazu Tanigawa ◽  
Izuru Kawamura ◽  
Teruaki Fujito ◽  
Motoyasu Sato ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Microwave Heating ◽  
Liquid Crystalline ◽  
Local Heating ◽  
Heating Mechanism ◽  
Non Equilibrium

Non-equilibrium local heating states in the liquid crystal MBBA were observed using in situ microwave irradiation NMR spectroscopy.

Mechanism for microwave heating of 1-(4′-cyanophenyl)-4-propylcyclohexane characterized by in situ microwave irradiation NMR spectroscopy

2015 ◽  
Vol 254 ◽  
pp. 27-34 ◽  
Author(s):  
Yugo Tasei ◽  
Takuya Yamakami ◽  
Izuru Kawamura ◽  
Teruaki Fujito ◽  
Kiminori Ushida ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Microwave Heating

Annealing effects on the electrical conductivity of polymerized liquid crystalline 3,4-ethylenedioxythiophene derivatives

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Noelle Wrubbel ◽  
Helmut Ritter ◽  
Knud Reuter ◽  
Alexander Karbach ◽  
Doris Drechsler
Keyword(s):  
Electrical Conductivity ◽  
Atomic Force Microscopy ◽  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Electrically Conductive ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Annealing Effects

Abstract3,4-Ethylenedioxythiophene derivatives with aromatic, in most cases mesogenic, side groups were synthesized and their liquid crystal behaviour was characterized. These monomers were polymerized oxidatively to charged, electrically conductive polythiophenes. X-ray and atomic force microscopy studies were performed. Films of theses polythiophenes achieved via in situ polymerization were prone to a significant increase of the conductivity by annealing.

Efficient, microwave-assisted intramolecular 1,3-dipolar cycloadditions of oximes and N-methylnitrones derived from o-alkenylmethoxy-acetophenones

2005 ◽  
Vol 83 (3) ◽  
pp. 260-265 ◽  
Author(s):  
Surinderjit Singh ◽  
M PS Ishar ◽  
Gajendra Singh ◽  
Rajinder Singh
Keyword(s):  
Microwave Irradiation ◽  
Microwave Heating ◽  
Reaction Times ◽  
Solvent Free ◽  
Dipolar Cycloadditions ◽  
Microwave Assisted ◽  
Solvent Free Conditions ◽  
A Minor ◽  
Acetophenone Oxime

Contrary to literature reports, the o-allyloxy- and crotyloxy-acetophenone-oximes (2a, 2b) are transformed to nitrones, which undergo regio- and stereoselective intramolecular 1,3-dipolar cycloadditions, both on microwave heating under solvent free conditions and refluxing in toluene, to afford novel cycloadducts (5a, 5b); the oxazepine-N-oxide (3a) reported to be formed in 98% yield was obtained only as a minor product (~10%). However, o-cinnamyloxy-acetophenone-oxime (2c) under similar conditions undergoes intramolecular N-alkylation to afford nitrone (3c). The reactions carried out under microwave irradiation are cleaner, require shorter reaction times, and have higher yields. Corresponding intramolecular 1,3-dipolar cycloadditions of N-methylnitrones (B), generated in situ from o-alkenylmethoxy-acetophenones (1a–1c) and N-methylhydroxylamine under solvent-free microwave irradiation conditions, are completely regio- and stereoselective, require much shorter reaction times, and afford adducts (4a–4c) in higher yields, as compared with their thermal counterparts.Key words: cycloadditions, nitrones, oximes, o-alkenylmethoxy-acetophenones, microwave, isoxazolidines.

scholarly journals Wavelength-tuneable laser emission from stretchable chiral nematic liquid crystal gels via in situ photopolymerization

RSC Advances ◽  
2016 ◽  
Vol 6 (38) ◽  
pp. 31919-31924 ◽  
Author(s):  
S. M. Wood ◽  
F. Castles ◽  
S. J. Elston ◽  
S. M. Morris
Keyword(s):  
Liquid Crystal ◽  
Nematic Liquid Crystal ◽  
Liquid Crystalline ◽  
Laser Emission ◽  
Mechanical Strain ◽  
Chiral Nematic

We describe a technique for creating multi-coloured liquid crystalline laser gels which may be selectively and reversibly wavelength-tuned by applying a mechanical strain.

Optimization of Interfacial Modification by Microwave Irradiation: Evaluation by Dimensionless Number for Non-Equilibrium Local Heating

2020 ◽  
Vol 46 (5) ◽  
pp. 161-166
Author(s):  
Yosuke Shibata ◽  
Satoshi Sonobe ◽  
Kiyuki Saiuchi ◽  
Yusuke Asakuma ◽  
Anita Hyde ◽  
...  
Keyword(s):  
Microwave Irradiation ◽  
Local Heating ◽  
Dimensionless Number ◽  
Interfacial Modification ◽  
Non Equilibrium

The True Liquid Crystal Approach to Mesoporous Silica

1996 ◽  
Vol 425 ◽  
Author(s):  
George S. Attard ◽  
Mark Edgar ◽  
James W. Emsley ◽  
Christine G. Göltner
Keyword(s):  
Liquid Crystal ◽  
Nmr Spectroscopy ◽  
Mesoporous Silica ◽  
Liquid Crystalline ◽  
A Priori ◽  
Lyotropic Liquid Crystal ◽  
Crystal Phase ◽  
Deuterium Nmr ◽  
Liquid Crystal Phase ◽  
Ceramic Oxides

AbstractLiquid crystalline phases, consisting of nonionic surfactant and water, are exploited as templates for the synthesis of inorganic nanostructures In this approach the aqueous domains of a lyotropic liquid crystal phase function as a confining medium, in which the polymerisation of a watersoluble precursor takes place without destroying the nanostructure. Conducting the prepration of mesoporous silica in a lyotropic liquid crystal phase has considerable advantages over previous routes towards mesoporous ceramic oxides. (i) The nanostructure of the solid can be predicted a priori by knowing the phase structure of the liquid crystal before solidification, (ii) this approach allows the use of nonionic surfactants as templates, (iii) the progress of the reaction can be observed by a variety of methods, such as polarised light optical microscopy, X-ray diffraction, and deuterium NMR spectroscopy, all of which are noninvasive. The synthesis and a new way of monitoring the temporal evolution of the inorganic nanostructure using deuterium NMR spectroscopy are described. The results show unambiguously that the lyotropic liquid crystal phase acts as a template for the nanostructure.

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