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Show moreQuadrupolar and octupolar invariants may be used as methods to attain noncentrosymmetric materials for application in second order nonlinear optics. The structure-property relationships for the J = 2, or quadrupole rotational invariant, are investigated. Proper citation for the Technical Digest CD-ROM should be written in the following format: Ostrovekhov V., Ostroverkhova O., Petschek R.G., Singer K.D., Sukhomlinova L., Twieg R.J., “`Quadrupolar' molecular nonlinear optics,” in the Conference on Lasers and Electro-Optics (CLEO)/The International Quantum Electronics Conference (IQEC) (Optical Society of America, Washington, DC, 2009), Proceedings, 8-9
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Mandel School of Applied Social Sciences, Case Western
Show moreFrom the American Humane Association, 1999 Family Group Decision Making Roundtable Proceedings.
Mandel School of Applied Social Sciences, Case Western Reserve University
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Show moreWe investigated 1:1 mixtures of a variety of 4,4′-disubstituted diphenyldiacetylenes (PTTP series) and cyano-containing mesogens for possible complex formation Complexes were formed when alkyl/alkoxy cyanobiphenyls (CB series) were mixed with alkyl/alkoxy PTTP homologues. We found complexes having a melting temperature higher than that for either component, and complexes with lower melting temperatures. A fluoro substituent on the PTTP gave an enhanced nematic phase and a cyclohexane ring in place of a benzene ring yielded an enhanced smectic A phase, but a cyano on the PTTP gave poor liquid crystalline properties. Phase diagrams were constructed for PTTP-24/5-CB and PTTP-24/8O-CB mixtures. Both complexes formed had melting temperatures higher than those for either component. These complexes were recrystallized and shown by X-ray studies to be 1:1 complexes. The PTTP-24/5-CB complex showed only a monotropic nematic phase, but the PTTP-24/8O-CB complex showed induced smectic A and hexatic B phases in addition to an enantiotropic nematic phase. ©1999 Taylor & Francis Ltd.
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Show moreOrganic chromophores have been exploited for a wide range of discrete optical and electronic functions as well as a growing number of combined opto-electronic functions. We are pursuing development of organic and polymer materials for a range of applications that require properties including liquid crystallinity, second order optical nonlinearity, photorefractivity and, more recently, special nonlinear optical behavior involving molecular chirality. On publication the full bibliographical details of the paper (Proceedings 561(1999), 119-130) must be inserted after the journal title, along with a link [http://journals.cambridge.org/abstract_S1946427400208403] to the Cambridge website address for the journal. Inclusion of this version of the paper in Institutional Repositories outside of the institution in which the contributor worked at the time the paper was first submitted will be subject to the additional permission of Cambridge University Press (not to be unreasonably withheld).
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Show moreSecond-order nonlinear optical (NLO) polymers, which polymers are functionalized with second-order NLO chromophores, offer advantages of large susceptibilities, high laser damage threshold, faster response time, a high density of NLO moieties, versatility of molecular structural modifications, improved processability and relatively higher thermal stability compared with small molecular weight organic materials. The design, synthesis and characterization of novel elastic-polymer containing NLO chiral conjugated chromophores based on the derivatives of chiral camphorquinone, which would be expected to display large three dimensional polarity and more thermal stable NLO optical materials are discussed.
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Show moreThe optical retardation of a liquid crystal above the nematic-isotropic phase transition temperature TNI and subjected to planar alignment conditions at the substrate was investigated in the presence of an electric field applied normal to the substrates. The response was found to exhibit "S"-shaped behavior with electric field, and was larger near TNI than well above TNI. The results were examined in the context of a model that permits both biaxiality and a field-induced tilt of the molecular director. The results suggest that the primary effect of the electric field is to induce biaxiality, and in consequence suppress the order induced by the surface. No clear indication of a Freedericksz-like transition, either experimental or theoretical, was observed. Appropriate bibliographic citation and notice of the APS copyright must be included- "Kim J.-H., Petschek R.G., Rosenblatt C., Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics 60:0.208333333333333, 5600-5606 (1999). Copyright 1999 by the American Physical Society."
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Show moreIn this paper we develop a self-consistent model for the equilibrium statistics of nematic branched polymeric liquid crystals in the mean-field approximation. We have solved the resulting system of equations numerically and find a nematic-isotropic phase transition. We find that the order-disorder transition temperature scales as a function of the bond continuation probability, or equivalently the molecular weight, with an exponent that depends on the interaction potential. These results are compared with the experimentally observed behaviour. ©1999 Taylor & Francis Ltd.
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Show moreDigitized exhibition layout map, part of the Museum of Contemporary Art Cleveland Archive collection (Spec-Coll-00080) -- Series 2: Exhibit files, 1969-2011 -- 1998-2000 -- Faster Than a Speeding Bullet: Superheroes in Contemporary Art, 1999 (box 21, folder 16).
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Show moreDigitized pickup and delivery schedule, part of the Museum of Contemporary Art Cleveland Archive collection (Spec-Coll-00080) -- Series 2: Exhibit files, 1969-2011 -- 1998-2000 -- Faster Than a Speeding Bullet: Superheroes in Contemporary Art, 1999 (box 21, folder 16).
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Show moreDigitized exhibition checklist, part of the Museum of Contemporary Art Cleveland Archive collection (Spec-Coll-00080) -- Series 2: Exhibit files, 1969-2011 -- 1998-2000 -- Faster Than a Speeding Bullet: Superheroes in Contemporary Art, 1999 (box 21, folder 16).
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1999, No. 14